Elon Musk is sketchy for so many more reasons than this.
Also, it's not like this is something that Elon Musk thought up by himself with his evil mastermind brain or something. Here's a very popular YouTube video (16 million views) on the subject from 9 years ago that makes basically the same point:
As someone who works in an educational field that uses AI on every single shift, the video is correct (though I don't know about some of Musk's particular economic predictions that are obviously not covered there; he's not an economist, and he thought the "Cyber Truck" was a good idea, so I don't trust his judgment on a more basic level). There is very much a sense at my job that we are kind of training our 'replacement', as the AI we use is getting markedly better with each iteration, but it's nowhere near where it would need to be to be deployed with no human oversight, so our jobs are safe for the foreseeable future. In the long term, however, I don't doubt that a great many jobs (including mine) will ultimately be assumed by a more advanced AI. This will require a great amount of reconsidering the foundations of modern economics, but I guess I naively hope that by the time we're at that point, everyone will have seen the writing on the wall for quite some time, so there won't be as much of a fight anymore about how all us little worker bees just need to get back into our job-holes, because...well,
what jobs? Presumably the people who would be arguing that now (the owning class) will be the ones who most benefit from being able to replace all their workers with AI, so it doesn't really make sense that they would be also be the ones telling everyone to get back to work. Maybe it'll be like living in Alaska, where the government just gives you money for being around. Who knows. We're definitely not there yet.