Does adding a trivial word filter even make any sense from a legal point of view, especially when this one seems to be filtering out words describing concepts that can be pretty easily paraphrased?
A regex sounds like a bad solution for profanity, but like an even worse one to bolt onto a thing that's literally designed to be able to communicate like a human and could probably easily talk its way around guardrails if it were so inclined.
I dunno if it meets your definition of legal, but "The EU Code of conduct on countering illegal hate speech online" seems to largely hinge around putting in effort to combat such things. The companies don't have to show that the measures are foolproof, they just show that they're making an effort.
