Well, if enough people express disapproval, it is something you've done. Often is isn't something that can be articulated. Frequently it is the tone in the posts. Sometimes it's just "something" that rubs people the wrong way.
If you don't like the way people are reacting to you, you can a) complain that it isn't fair, and insist people change how they react to you, b) change yourself.
Look at the posts of the people who are generally well-regarded and well-liked and see how the differ from yours. You'll be able to tell.
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