What about the famous case of Carlsen claiming that his opponent cheated and even forfeiting to draw attention to it?

This is a big part of the problem... Kramnik had been bullying people for years about cheating, including aggressively bullying Daniel Naroditsky, and for the most part the chess community did nothing about it. It would be very hard for people to condemn Kramnik for his cheating accusations all the while chess' top star Carlsen was on a bullying spree of his own against Niemann.