I have seen this in practice here. Probably for a variety of reasons. First and above all, things in writing can misconstrued very easily, especially if not clear in the first place. Probably wise to consider all comments and response carefully when placing to make sure all clear.
Secondly, with differing points of view, experience and focus, very easily to misunderstand what a poster is trying to say. Added to that, people are people, we all come with our own challenges. Some may be resentful or jealous based on perception. I try never to take criticism personally, but I will say I have seen it at play here.