Most people these days hate Nazis for what they did. Hating someone for what you think they might do is your thing.
Another reason people hate Nazis and not Muslims: Nazis were a centrally organized body with a 'high command'. If someone identified as a Nazi you knew what they stood for -- they were facists, after all.
Meanwhile there are 1.8 billion Muslims in the world and no central authority that represents them all. It's pretty hard to hate such a large, heterogeneous group.
Holy crap that isn't even close to what a fatwa is lol