Yea mein kampf doesn’t need a evil writer to be evil. It would be evil if it was anonymous or ghost written. Other art by Hitler would have been a better argument as it is just a picture of a city or building and doesn’t have any racist or antisemitic content but still is stained by him in its story.

I think it’s meant to be criticising people who just say “separate the art from the artist” for things like Harry Potter, but them pointing out the hypocrisy with a book that no one can defend because of who wrote it. That’s my take, anyway