“Esp. 1) if anyone can be watching. When you think about it, you might realize it can be quite a 2) hurtfull topic for some…”
OMG, they know! 
I am not sure how calling someone a Polish, Finnish or Jew etc hurts them exactly? Oh, I am so offended by “blaa blaa blaa” is all in offended ones head. It’s his/her decision to be offended. It can be literally anything.
For example, letter “A” offends me.
Now what?
It’s quite simple, now you have to find a community that thinks the same, or adapt. We as a community here agree that we do not like (what we percieve as) racial comments. Debating whether it’s good or bad is irrelevant. Those are our rules. If you feel like you need to able to have such freedom in the chat that’s okay, but you will not be accepted here. You can look elsewhere or start your own server with such conditions.
That escalated fast to “start your own” 
Unfortunately, I do not know about a server that aggrees that the letter A is offensive, thus I am afraid starting your own server might be the only choice.
It’s not about offense. Antisemitism harms people. You should stop.
This seems like a good place to stop.