Not to get too political, but it is breaking down and it has been for a while. Part of it is just temporal distance, part of it is non-western cultures becoming more relevant, and part of it is that it's something of a luxury belief these days. Like it or not, Kanye still has legions of fans and the things he says do influence people. If Kanye says that Hitler was a good guy, that's all a lot of people need to convince them to drop a belief system that was already waning in the face of changing cultural and economic times. It's hard to give a shit about something that happened nearly a century ago halfway across the world when everything in front of you is falling apart.
I have a feeling this isn't the last we are going to see of various famous people, especially black artists, publicly adopting Nazi/Hitler-sympathetic viewpoints. It's probably just the start of it. After all, who owns the entertainment industry? Who owns the record labels? Who controls which artists get promoted or not? Who did Hitler have the biggest problem with?