The ADL's current leadership appears to be ideologically aligned with Elon Musk for reasons unclear. Here's an article with other Jewish voices, including the former director of the ADL, emphatically stating that it was a Nazi salute: https://forward.com/fast-forward/690745/adl-elon-musk-sieg-h...
As for his other views, Wikipedia can speak to it better than I can: https://en.wikipedia.org/wiki/Views_of_Elon_Musk#Race_and_wh...