Background
I work in an open space and people there chitchat fairly often. I do it, my coworkers do it and everyone is fine with that (even if it can be a bit annoying IMO).
Today, one of my coworkers was chitchatting with another one and their chat was making me very anxious. They were talking about discrimination and there was some friction between them (they weren't really arguing, but not really agreeing either).
Since I didn't know how to politely ask them to go chat elsewhere without being seen as a killjoy, I ended up leaving the room (hoping that they would have finished talking about that when I would come back).
Question
How could I have asked them to go chat elsewhere without being seen as a killjoy?
Or without being seen as "fake" because I also chitchat in the open space about those topics sometimes?
My relationship with those coworkers
One of this coworker (let's call them "Alex") is my "work-neighbor" (sitting next to each other) and we have a nice relationship. We chitchat often and even talk about discrimination together (which I'm fine with, especially because we share the same point of view so talking about this isn't tiring for me).
Alex doesn't know that I have anxiety issues but I wouldn't have a problem disclosing it to them.
The other coworker (let's call them "Otty") is new here. They are very polite and seem nice (from what I have seen so far).
Otty doesn't know that I have anxiety issues either and I am not planning on telling them (because I don't know them enough).