There are various levels of increasingly broad problems of increasing severity you actually adress here and I'll try to look into them step by step. I warn you right away that I can't really back all the things said herein by proper statistics. Much of it is an admittedly subjective assessment of the community's condition that might as well be entirely wrong.
The current problem of low-quality contributions
Part of what you experience might actually be a somewhat seasonal trend. As said I can't really back this, but in my experience this period of the year is generally one of rather lowered activity and lowered high-quality contributions. I don't say (and I'm sure you don't either) that we don't get any good questions and answers right now, but the start of the year has also been a rather down-putting period in previous years. This might be due to various factors, from people getting out of their new year vacations to a decreased output of actual high-quality content in some of the major film industries we serve here. To some degree we are a bit of a seasonal site.
This isn't to say the problem is just to be ignored and will go away when we just sit it out. Bet sure it won't, and bet sure this is not the end of this answer. But it is one possible factor.
The problem of low-quality identification questions/answers
This specific question category and its problems has actually been adressed already in previous questions, together with some possible approaches for solving some of those problems. I'll not rehash the entire post here and would rather encourage everyone interested in the matter to pay a visit to those questions and their answers and maybe even come up with new answers.
But this is not a particularly new problem, but one that the site has been plagued by for quite some time now. It might, however, surface even more in the absence (or decrease) of other high-quality contributions to contrast those posts (which brings us again to the other factors).
I'll also admit that since asking this mentioned question not that much has been done by the moderators to consider or implement some of the proposed solutions from the answers, apart from a few little improvements of tag wikis and help center articles and a keener eye on ID questions. While the moderators are not the only ones to care for the community and to tackle problems with the site and can only do so much in addition to their non-site life, they should still be in the forefront of showing initiative for improvements, especially if they involve possible technical changes not accessible to normal users. We didn't, I didn't, or at least not as much as I could have. Although I asked that question, I've not yet made much out of its answers. With the new light your post shines on this issue, however, I hope to find some new initiative to tackle this problem, and maybe inspire one or the other user to do so, too.
The general state of the community
So, please sit down now. I will possibly diverge quite a bit. What you adress here indirectly is actually a larger problem that I have noticed for some time now. But as with other things, I have kept ignoring it and hoped for the best. With your question however, coupled with the fact that tomorrow marks the 1st anniversary of this site having graduated, I'll have to face it. However, as said the following is largely subjective, neither is it meant too pessimistically rather than realistically and under the prospect of improvement. But I feel this community is a bit in decline and that for quite some time already.
Now this may sound harder than it is. But having seen this site from its earliest inception onward, if I remember back to older times, say 2 years ago, I can't help the feeling that this site spawned more insightful questions, spawned less ID questions and, maybe above all, was more active, featuring highly avid users and many questions and answers that got highly voted. It is a feeling that I also have each quarter when trying to assess the favourite questions and answers of that quarter. I always find good stuff, but also can't help the feeling that the selection gets more difficult each time.
What I don't want to do, though, is in any way to talk our current community down. We are not lacking in good and insightful questions and answers, neither are we lacking in engaged users. We have many very good users, some of them rather new, and the last thing I want is talk their contributions down. Neither is this site at the verge of dying, by far not. However, seeing many of those users decrease their activity over the years is something that can shade one's judgment of the user base's development, even though it might be a natural developemnt with new users filling their places.
This IMHO correlates directly to meta activity. There is a very close core of users who actively contribute, but also who actually vote, on meta. While this isn't necessarily a bad thing in itself, it is not too good for a healthy site when the group of people actually governing it shrinks more and more, especially when seen in comparison to previous times when meta activity was higher. Now this might be due to various factors, be that a generally higher interest and importance for meta discussion during the site's earlier days. But it might as well be a decrease in interest or downright man-power among the active user base.
So where is the problem to be searched for then?
It is not that easy to say what actually is the cause for this problem. While Richard adresses some valid points in his answer, that we should keep guiding new users and possibly poor questions to improvement by editing and offering advice, this is often done on this site. I often see comments asking for clarification with unclear or poorly-phrased questions. Others make edits to improve questions, sometimes even from closability into reopenability. The problem of not enough voting, say compared to other more active sites, might as well come down to the same problem of decreased site activity mentioned above.
I know not everyone might agree with me on this or might see this as a lame excuse, but I do see the primary quality problem for this site, and the danger for its well-being, in identification questions, now more than ever before. It is a problem we always largely ignored until we allowed it to get out of hand. As explained in previous assessments, the influx of ID questions is not only as large as never before, it is also increasing.
And while they on the one hand have the known problem of bringing many low-quality questions with them, they IMHO also have the maybe even heavier problem of simply distorting what this site is about. Their viral nature, which only leads to more ID questions and builds a subspace on this site that grows and grows while it doesn't represent the site's primary purpose, deteriorates the brand of what this site is. This site has never been a site about movie identification, that was always only a service offered by a site about generally discussing films and their aspects. Yet this task is what we primarily do now and what people will see when they come here.
So it encourages more and more of those questions, with their usual sub-par levels of quality and insightfulness and their usual sub-par levels of binding users to this site and turning them into avid and valuable contributors. And even more so this IMHO additionally discourages users interested in insightful and engaging questions and not interested in a mere quiz-show site from participating, which leads to a decline of activity and interesting non-ID questions in addition to a rise in low-quality ID questions.
And this again leads to a certain exhaustion of users engaged into the site and its well-being, by flooding them with low-quality posts. This in turn leads to many very lowly voted questions and answers. But while these might in turn scare away people from this site, it is, as explained in previous meta discussions, not a solution to simply be more lenient with bad questions as that won't help to improve the quality of contributions either.
And what to do about it?
Well, first of all, let me assure you that the above ramblings might sound more pessimistic than they really are. I still believe that this site is one of the best inventions since sliced bread and my devotion to it has not shrinked the slightest since its ealiest inception. In the same way do I think that we are still a constant source of great, insteresting and insightful questions and answers about films and TV-shows. But I'd also like to keep it this way.
Besides that I can't really offer that many clear solutions of the form "apply this comment for such a question" or "vote to close questions that mention this" or "edit this word out of answers". Richard has already given some good general points where the site could improve handling new users and their possibly sub-par first posts, even though I think that we already do this to a large degree. In general I would like to encourage the user base at large to more participation. I know this sounds awfully vague and indefinite and many of you already go out of their way to improve this site. But always remember the little things:
- See a problem with a question that's easy to fix? Make an edit (suggestion)!
- See an answer that could use some help? Consider editing it rather than downvoting, if possible!
- See an interesting question that is worded a bit unfortunate and opinionated? See if you can come up with an alternative phrasing that might make it less opinionated!
And in between never forget to vote, vote, vote! Be that upvotes for good stuff or downvotes for bad stuff. Voting is still our easiest and most vocal method to asses the quality of our content and thus hopefully shape the quality of future content. In addition to that, always remember that there is a place to discuss about the site and also one to ask people directly what to do or where to look.
- See some prevalent problem with the site? Take it to meta as Johnny Bones here he did!
- Want to have a say in how the site works? Give your votes on meta!
- Unclear what a policy actually is or where to find it on meta? Ask in chat!
And for addressing the specific problem of low-quality identification questions, take a look at the above mentioned questions that adress this point specifically and see if you agree or disagree with some of the possible solutions presented there, or come up with new ones.
And if you have some general input what the site could do differently or want to give your 2 cents about its state of affairs, you might also want to take a look into this (hopefully more optimistic ;-)) "where do we stand?" post graduation discussion.