He clearly does know how to make incredible sums of money. Why that's not enough and people need to find excuses to exaggerate or demean his intelligence is beyond me.
This is the insane thing to me. He's promised a lot of things, but he has also delivered some pretty huge things. Tesla kicked off the electric car migration and has millions of EVs on the road. SpaceX has reusable first stages on their rockets and are the only private company to send humans to space. Just those two things alone are massive achievements. But people look at some things he's promised but has not yet delivered and that somehow is more important than what he has delivered?
Here's two examples I've found particularly insightful that shows he has some ability to talk about engineering details.
This example where he talks about the choice of steel for Starship as opposed to any other metal, something that would be an otherwise unsual choice: https://youtu.be/vLC5W53Fsyg?t=936
This example that I've personally incorporated into my own thinking where he talks about his "five step process" for engineering design refinement (watch at least until he starts talking about Tesla Model 3 battery stuff): https://youtu.be/t705r8ICkRw?t=805
I knew what you were talking about when I started reading your comment. "Make your requirements less dumb" first seems so obvious once you've learned it.
All the denigration directed at him seems to come from people who've only read headlines about him from sources who hate him.
My guess would be that he has some knowledge but also is very good at faking it which is not necessarily a bad thing - those are good traits for a CEO. Though people should be aware of this fact when evaluating the whole persona.
Brute forcing a problem with better technology not always the actual solution when technical problems aren't actually the problem.