You seem insistent on it being "bad business", yet so is owning a private rocket company, or investing all of your money into an electric car company to try and compete with the likes of Ford and General Motors. I don't think Elon Musk cares as much about his bank balance as you and a lot of other people think he should. You seem continually baffled that a man who has consistently made very risky business choices continues to do that. Perhaps the logical explanation is that he did it for the reasons he stated. He obviously isn't worried about going broke, he's never going to be poor, it doesn't matter if you overpay when you're still the richest man alive (or there abouts)
The fact he managed to make a rocket company and Tesla doesn't mean anything in regards to twitter. I'm sure Hamilton is a great F1 driver, doesn't mean I want him taking the controls of a 747 when I'm in it (although how hard can it be for him, they're both vehicles that go fast and make a lot of noise).
You can be very good in one area, or at least get good people around you who can make you look good despite yourself, but that doesn't mean you're actually any good in other unrelated areas. and social media whilst being "tech" is not "pure tech" like rocketry.
People talk about rocket science being hard, I've seen rocket scientists say they don't necessarily consider it that hard, as long as they've got the resources and time they'll eventually get it to work as it's all pure science apart from getting the funding.
I've seen those same rocket scientists comment that they consider stuff that is social related much harder (such as politics and fundraising) as that involves human factors that they can't control. (rather like a social media platform!)
Musk seems to have thought (if he thought about the difference at all), that Twitter was going to be tech like Tesla, forgetting that Twitter in itself is quite a simple idea, it's the human factor that made it popular, the fact that it put people together so they could interact with each other, and then twitter could make money by selling adverts.
Unfortunately for musk pretty much the moment he started talking about what he wanted to do with twitter he worried the people that paid the bills for it, then he just went downhill from there.
For example, if pretty much every tom dick and harry could see that things like letting anyone buy the mark of a verified account was going to cause chaos, then how did someone who supposedly knows what he is doing miss that?
His interaction with Stephen King further showed that he didn't have a clue what he was doing, wanting to charge the people that create the content that he needs on twitter to keep the people that the advertiser want to see their ads showed he had no idea about how it was funded, of the basic premise of Twitter as far as it's users, both "normal" and "big name" were concerned.
Even now the whole tick thing is a farce, as what "paid for" verified gives you seems to be constantly changing (and people that have paid for it haven't got features that were promised), meanwhile he's gone from what was basically 1 verified identifier to about 4, and having complained about how cluttered the UI looked he's made it even more cluttered and hard to use (is that person verified because they are in fact a famous author, or just someone with a one use credit card number, dig three levels down to find out!)
Not to mention the whole thing where Musk didn't appear to know really basic tech related stuff, such as Apple taking a share of any money paid through it's app store (I'm not sure if anyone has pointed out to him Google do/did the same), and having a hissy fit about that.
