That's what Elon Musk has done since the start of his career and it has worked pretty well for him. For that you need to be a really good hype man because it's objectively true that great work that nobody knows about is pure waste. You need to be rich because in the US it's assumed that this means something awesome about you personally. You need to be the one who always announce the news on Twitter, you don't even have to lie, your strongest fan will assume you did all the work. Like they believe he is the founder of Tesla. Like they believe he is the real life Tony Stark. Like they believe that he, not the actual rocket scientists working at Tesla, design all those rockets. Like they believe that he invented the hyperloop when he renamed the vactrain concept from hundred years ago and then couldn't build it because it's bullshit. Like they believe he will save humanity by helping us anytime soon to escape Earth that people like him are destroying.
I don't really care about Elon Musk. The guy is a mix between a Tech Robber Baron and an emotionally immature 14 years old who has read too much science fiction. And remember more the fiction than the science.
OTOH his fan club is a fascinating experiment on how a cult of personality develops in public and in real time.
I don't disagree with your read on his lack of maturity, or that he takes credit for work he hasn't done, or that his fans believe he is singularly responsible for the accomplishments of his teams. However, it's odd that Musk is so obsessively hated. I believe his passionate detractors are under a similar polarizing spell as his passionate fans, only in the opposite direction of "hero worship".