That's more them covering their bases than really caring about what's said in chat channels (otherwise the profanity filter wouldn't be optional, and censorship would be hard-coded into chat like some other games do). It may vary by GM, but in general they're just going to tell you to blacklist them, which is a perfectly reasonable response considering that's the entire reason it exists. It's not defending people being "obscene", it's being realistic. SE gave us tools to help deal with disputes and if you refuse to make use of them like the OP that's your own fault.
