So many thoughts here.
I'm on the fence about whether he intended that to be the Nazi salute or not.
More telling, though, is his response. I'm not one for grovelling apologies for any slight offence by any means, but this not slight, and apology and backtracking is what is needed. He denies that it was intended, but has not felt to make a heartfelt apology for making such a grave error, instead using the fact that he has been criticised for it to attack his opponents.
Prominent right-wingers, meanwhile, are celebrating, and I fear we are going to see more such salutes, both on the streets and in political contexts.
Whether you believe he intended the salute or not, to make light of this major shift seems short-sighted at best, particularly by these public figures. And I say that as someone who supports their stance on women's rights.
Lastly though, OP, if you have a problem with Musk, get off X now, and deny him the oxygen of your engagement and the financial support. This is the one small, simple thing we can all do now to stand against him.