Are non-helpful negative comments typical of this site?

Question

This isn't a complaint; I'm just trying to understand what's going on with this site, which I joined only 2 days ago.

My first answer, The usage of "would have", received a comment effectively saying I'd plagiarized another answer. That other answer began with "Actually, the answer came to me first and then Google searching this question followed. When somebody has in in their destiny that if a certain environment happens, they would …", and I didn't even bother reading the rest of the incoherent block of text, much less steal its ideas.

My second answer, Flying since numbers/for a number of years, quickly received 4 down-votes and a useless comment: "The answer's right but the reasoning is way off the mark.". If an answer is bad enough to immediately get 4 down-votes, surely at least one of the down-voters should indicate what was wrong with it. As it is, if I weren't already well involved with other sites, I suspect that I'd leave and never bother with Stack Exchange again.

As I said, I'm new to this group, so my answer may very well be worthy of 4 down-votes, but it would be nice to know why, so I can correct or delete it.

My question is, is this typical for this site, or did I simply encounter a bad day?

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Update: I now notice that one of the answers to the second question had a "discussion" that has been moved to chat, and one of the others is in the middle of another discussion.
(I'll guess that this really is a bad day (or at least the result of a not-so-well worded question).)

Answer 1

The response you got on your first answer is quite odd. I'm sure it happens from time to time that users accuse each other of having stolen their answers, but I don't remember seeing it. Sorry this happened.

As for your second answer, this is more typical. There's two issues. First, when people downvote, we encourage them to leave constructive comments, but in general, people here are conflict-averse, and don't want their user names involved in negativity, so you just get the downvotes. When this happens to me, I leave a comment asking for feedback and often I get it. Also, among people who do feel confident enough to leave comments, not everyone is great about communicating what the problem is in a helpful way. This is quite different to the tech SE sites, where explaining why someone's wrong is part of the culture.

The second issue is that your answer, in fact, is not great. Sorry :). The OP asked how, given that particular sentence, to choose both between "for" and "since", and between "a number" and "numbers". This is a question of grammar rules. The correct form is, "...for a number...", and a good answer would have explained the rules why. However, your answer is about the difference in function between time expressions with "since" and "for", and about the semantics of that particular situation, so it doesn't even answer the OP's question about grammar rules. My guess is that's why you got downvotes, but without any comments to go off, I'm just mind-reading here.