It is difficult to find a really satisfiable course.
The trouble already starts with the question : When is a downvote or a close vote the right reaction, when not?
I understand that homework-questions where the OP shows absolutely no effort and additionally more or less demands an answer, are not welcome here.
The problem is that many users seem to post an answer nevertheless more or less automatically because they want to increase their reputation. And it often works!
High reputations lead to strong privileges. It is debatable whether all this privileges are useful for the site.
Now, the next problem. The site expects to show some effort or to give a source. The askers who present a try of a proof of a famous conjecture might be convinced that they solved it!
If I understand the rules of this site correctly, the behaviour is not against those rules.
Another thing is, that it might appear annoying that people actually think they have solved a very difficult problem , although the probability that they actually did is very small.
You can argue that such questions are not in the scope of this site, that it is too difficult to find a refutation, for example. But this is not always easy to justify. Maybe, the OP had an interesting idea, which at last fails.
What is much more annoying for me is that questions like "Is 1 a prime number?", which could be answered by a simple remark and nothing more, receive many answers. Moreover, the question and the many answers usually receive tons of upvotes.
Additionally, very short answers , sometimes containing only a very small hint, are often upvoted massively which is unfair, in my opinion, against answers which caused the answerer much effort and a long time to solve.
Reputation and the resulting privileges are not bad in principle, but since the upvotes, downvotes, closevotes are necessarily more or less subjective, this can sometimes lead to effects that are in contrast to the invention of the site. I do not see a way to solve this dilemma.