The amount of self-control it takes for people in these positions to restrain themselves is fascinating. Musk seemingly has very poor impulse control, and he veers all over the place accordingly, with the wealth and fame doing the classic thing and amplifying.

Steve Jobs could have veered all over the map. He was anointed with the title of genius by the public broadly (and Jobs may have indeed been a genius at what he was great at, narrowly speaking). He successfully rebuilt a globally iconic company and his leadership resulted in Apple producing extraordinary products that hundreds of millions of people have enjoyed. He was also one of the richest people in the world when he died and quite famous. Instead of veering widely, he had the self-control to stay on task, stay focused, and more or less had the discipline to not veer far outside his sphere of competency. The self-control to stay on task seems to have been something Jobs intentionally made himself get better at over the years. He recognized the more important thing was to do fewer things and do them well and he preached that to anyone that would listen. He recognized that our time limitations (and time-productivity limitations (you can only be highly productive for a fraction of a day)) are aggressive, so you're better off focusing heavily rather than sprawling. We're quite finite in our capabilities, at best. Even when Jobs was doing Pixar, he was very careful not to go too far away from focusing on Apple, and he didn't attempt to keep sprawling his focus even though he easily could have (this is a big separation for Jobs and Musk; maybe someone with high productivity potential can do an Apple + Pixar simultaneously, with good management; do more than that? I think Musk has potently found the point of imploding returns on sprawling focus).

Musk is at risk of producing a lot of duds as he sprawls his focus, and maybe he doesn't care if that happens, however there is a significant time-productivity cost to what he is doing (and a huge monetary cost). The Twitter time and $40 billion could have been spent on getting to Mars. $40 billion would probably get SpaceX to Mars. This is something that makes me understand why some people like to hurl invective at him. Guy spends two decades with a supposed overarching goal of chasing Mars, acquires a quarter of a trillion dollars, some of which he can liquidate to accelerate the mission, and then he does this. Talk about veering off. Jobs would have sold $20 billion of Tesla and pumped it into chasing Mars, if that were his primary goal.

Despite how much certain people hate Musk now (in the same way they hate Trump, and for similar reasons), he is brilliant at what he's good at. No matter how much his detractors wish to tear him down, and no matter how much he makes it easier for them, it's simply true that he is a very intelligent person and at least narrowly highly competent. Most of the HN crowd would instantly vaporize when confronted with what he has taken on over the past 10-15 years (being worth $200+ billion and globally hyper famous would melt nearly everybody on HN, and that's just one point). Trying to do things well outside your competency, when you're already stretched thin on your primary mission/s, is a very bad mistake of impulse control / focus. Your line: "Why is it assumed that this guy who has no background in this industry knows what he's doing?" pretty well nails it. It reminds me of the average Joe thinking they have an idea for a restaurant or bar, and that that'd be a great business to pursue (because they've eaten at restaurants before and like most people they have strong opinions on food/service); Musk's mistake on Twitter comes from a similar place, he was a heavy social media user just as Joe eats at restaurants.

Musk will require another beating (akin to Tesla and SpaceX nearly failing simultaneously) to pull his focus back to Earth. Otherwise he'll just continue to sprawl, his impulse control is too mediocre to self-impose that course correction without hefty pain prompting it. Something sharp and negative has to affect him, in proportion to his financial capabilities and or something very bad has to happen to Tesla or SpaceX. Maybe he'll remain hyper rich and just waste his twilight days sprawling around, either occasionally getting in the way of the SpaceX mission or being fortunate enough that it succeeds in spite of his erratic approach.