I don't think I've ever seen them accept an apology. They always demand one, and never accept it.
I still don't understand what's so horrible about "I'm sorry to those offended." It's as though folks are upset at the reality that not everyone was upset.
No see, the point is that if you say "I'm sorry if anyone was offended" it's basically victim blaming.
You're supposed to say that you're sorry for being a horrible hateful person and you promise you'll go to workshops to learn how to be better.
And maybe, MAYBE you will be forgiven one day.
Or more likely, people will have moved to a new thing to get offended by.