This is a political play.
Musk may be a competent engineer, but he's used to being Emperor. He's completely out of his depth with culture and politics. So he's unprepared for the brutal muck-racking, humiliation, and character assassination that underpin political power games.
The "You can have free speech for just $8/month" accidental branding is already such a bad look. I don't see that he has the instincts, talent, or experience to even understand why - never mind to do better.
What has he personally engineered. He's an 'ideas guy' and maybe a manager.
Tesla, saving the work through EV
SpaceX, projecting humanity into the cosmos
Twitter, ?
Twitter is boring. Its explosive growth days are behind it, working there now is basically about maintaining a legacy platform that has a bunch of problems that mostly aren't technology problems. It's about as interesting as working for a big insurance company; if the paycheck and working conditions aren't there, you're not going to be able to attract talent.
The difference might be in the fact that Musk founded it and allegedly takes part in the recruitment process himself. Maybe he wants to do the same at Twitter. Turning an already existing company with an already existing company culture around is much more complicated, though.