Merlion, I have suffered some bad situations here too time and again, what i have learned is that some people contribute while others prefer to show that you are wrong and they are right, either because of your lack of vision or something else, this happens anywhere anyway, just that here we feel more cheated because we like the hobby so much.
Personally I would not go away because of that, I would ignore those posters and keep life going on, one good way to make them change is to act politely and ask them to do the same, say you are sorry if they got offended by anything and things might go well. or not.
Personally I think that saying your point is laughable because of anything is somehow offensive, to me it is far from counter argumentation and so I see how you feel. I would never leave anywhere for that though, I have decided some time ago in a very bad incident that I suffered that i wouldn't keep good things away from me because of people I dislike or that despise me, they are not worthy all that, in my opinion.
Anyway, on the posting on public forum and all, you are still the author, you are still the only one able to seel the rights, else someone is incurring in a crime. If it is game mechanics, though, what you post is more often that not considered OGC and so can be used as they wish, although you are the author, and so they have only one restriction, to give the author his credit.
Posting ehre does not render anything unpublishable, on the contrary, it might raise interst in it and make it be published, like Nyambe and the Tome of Horrors, for instance.