Musk isn't receiving credible rape and death threats at nearly the level of Swift (if he is at all, let's be real) by people who are known for following through on such threats.
Look, I even empathize a little with Musk regarding that specific situation. If I were in his shoes, I also wouldn't want an app like that to exist. I don't think his situation warrants any kind of action to stop it because it's really just an inconvenience for him. And he knew that it's just an inconvenience, so how he handled himself from day to day didn't really change.
For Swift, this is legitimate fear. I don't know if you've ever experienced actual fear for your life, but it's crippling, and it effects your psyche.
To experience that on a daily basis because of an app? You bet your goddamn ass I'm going to talk to my lawyers about what my options are.