It's impossible to make a club for each and every, every club has its rules and you accept them and stay or decline them and leave. Of course you can try to change rules, but it will limit someone else's opportunities anyway.

When you say that I can't name the Celebes crested macaque as a black monkey I'm not sure why. If there are some people who want to hurt you with words and you are offended with some which could be prohibited, they'll use some other. Who wants to offend will offend, who wants to be offended will be offended. It is so easy to find something new just to offend someone. You know that usually some euthemisms become offencive in a time because intentions to offend can be masquerated under any words.

To be offended is a choice. To ignore offenders on some anonymous forum in Internet is also a choice. Instead of leaving the forum you can just ignore a user you don't like.