Is pointing out obvious plot holes really on topic? This question has a lot of upvotes, but to me it seems like a candidate for a "Yes, that was a plot hole." and a close vote. Even on the original question on scifi the answer is very discussiony. Kind of interesting, but not terribly useful.
Why don't Marty's parents ever mention how similar he looks to the Marty of 1955?
This type of sophistry is just a rhetorical questions disguised as being clever. Close as "not constructive."
Nobody really wonders why The Terminator didn't casually walk up to Sarah Connor and break her neck instead of shooting up a bar. It doesn't add to the understanding or enjoyment of the movie. I really hope this site has a bigger vision and simply closes these questions down as "not constructive."
This question already has an accepted answer from a moderator. Nevertheless, I'm going to dissent. I think that questions of this type can be very helpful, because often there is a valid reason for the apparent discrepancy that the asker just does not know about. It can be the case that subtlety can be interpreted as a possible plot hole.
Without knowing the answer, how can the questioner know if the question is an "obvious plot hole" or something else?
In 2001 and in Total Recall, the protagonists were exposed to vacuum, with very different reactions. One of these is a plot mistake. One is correct science. A question asking about the validity of these effects of this would be on topic for one movie but not the other?
Obviously, there are extreme cases, of course...but I think those would be voted down in the normal fashion.
Here is an example of a question that could have been quickly closed with a comment of "there was no point", but that then got a well documented answer that gives a clear and sensible real response.
