Can I take real world events that are yet to be made into movies and ask who would star in them? Or is that not allowed in movie tv SE?
No, I'm afraid idle speculation of this kind is not appropriate for this site.
We're not really a discussion forum to debate who our favourite casting choice for a non-existing (or even an existing) film would be. All answers to this will be entirely opinion-based nor would the question be of much use other than idle speculation and talking about your favourite actors and films. Granted, this can definitely be fun, it's just not what SE is for.
But...you can very well take discussions like that to Chat, which has much less restrictions about what we can talk about and how we can talk about it than the strict question and answer format of the main site.
No,this site is for asking and answering questions for real movies.
Those types of questions are not appropriate in the community, but there are other places specifically for those kinds of discussion questions.