Why? Because they still have a decent amount of support and don’t want to alienate their fans?
By 1936 it was clear that Hitler was a crazy narcissist. If people don’t speak out due to fear it becomes a self-fulfilling prophecy because everyone thinks the number of people supporting the narcissist is so much bigger than it actually is.
The best antidote against a narcissist is having the largest possible amount of people spending time with them 1:1 or in the same building anyway.