The legendary Celtic manager Jock Stein was protestant. When asked if there were two really good forwards up for signing and one was Catholic, the other protestant, which one would he sign? "Oh, I would sing the protestant one because Rangers would never sign the Catholic."

Yes it still exists but is nothing like as bad as it was years ago. For some reason foot ball does attract a minority of nutcases and most European teams have their "casuals" who just want to make trouble.
The joke in Glasgow is "I'm an atheist I support Partick Thistle"

It’s appalling. Freedom of speech should not include hate speech.

This is what religion does to people, turns them in to fucking idiots

As far as I am concerned, the players themselves can do much to alleviate the problem by banding the teams together in solidarity and asking their fans to cut it out.