It's part of being part of a large forum.
You get sane posters, mixed posters, off the wall posters and then some the world is ending posters. Your thread won't stop anyone from acting irrational towards the FO or anyone.
Posters will still post the stuff that annoys you. It's just how some act on here. Ignore it, block them or just don't click on their threads.
If he does, he's going to miss out on some of the best stuff that gets put up here.
We come here for different reasons. Some are just about the game, some are frustrated coaches or GM's, some are heavy into the X's and O's, some are as you say "off the wall" (my favorite group) but we are all the same is one regard, none of us likes being told what to put or not to put up here.
It's not my job to police what anyone puts up here but it is my choice whether to go into that thread and read it or respond to it. This is a sounding board, fans vent their frustrations and exercise their right to rant and I am fine with that because I am in control of what I read or write.
There are no limits on threads or on topics of those threads. To come to a fan site and not to expect to get complaints about everything and defense of everything is unrealistic. I do not agree with a lot of the posts/threads here but I do agree to their right to say it.
I am forever amazed at posters that will spend time to go into a thread, that they do not like or are tired of that topic, and actually be rude to the OP for starting it when all they had to do was pass it on by. Would they walk up to strangers in a conversation and chastise them for discussing that?
Anyone that sees a thread that they don't like just take the "talk amongst yourselves" approach.