I'm afraid I don't know who moderates the Steam discussion, but yes there is a report function (which I've just used myself now the post has been pointed out: the post and some of the discussion resulting from it certainly wouldn't be acceptable on these forums).
I'll also see if I can find out for future reference who does moderate there.
Thank you.
The only way for everyone to feel safe is to stop hate speech against everyone.
Edit: My comment did not come out sounding like it should have.