It's not a case of "some guy maybe did something that looked taboo."

Musk has a long history of supporting Neo-Nazis, and what many Neo-Nazis do nowadays is testing the waters with plausible deniability. If they cross the line, they backpedal and apologize. If they don't get backlash or if they groom their followers enough to be praised, then they continue or double-down.

You've misunderstood Hitler, he got lost in the moment because of his autism, making him hyperactively flail around with his arm and kill untold numbers of people in an unfortunate and accidental fashion that made it look like he was advocating nazism