10 years ago I was at a place where a new CEO came in and fired 80% of the tech team. It was a hard scramble for the surviving engineers, including me, and we had some episodes of being down, but we pulled through it and the site survived.
I think a balanced view of Twitter right now is that Elon Musk has made some mistakes, but in the end, Twitter will be fine, and in 6 months it might be more profitable than ever before.
The pros and cons work out something like this:
con:
Musk fired people recklessly, treating a global workforce as if it could all be treated under California fire-at-will laws. As such, Musk might face lawsuits and might have to pay out some damages. This is not a big deal. He has the money. He can pay.
Musk probably violated the consent decree that Twitter had with the FTC. Again, Musk will probably face a lawsuit and he will probably have to pay. Again, not a big deal, he has the money.
Musk fired or offered resignations to key team members. As such, in a crisis, Twitter may face some downtime. With key people missing, the ability to bounce back from a crisis will be slower than otherwise. But all this means is that Twitter will become unreliable again, as it was during the first 10 years of its existence. Not a big deal: it was popular even back when it was unreliable.
Musk fired or offered resignations to key team members. As such, the roll out of new features will be slower than it might otherwise have been. In particular, his roll out of subscription features will be slower than he wanted.
Musk could have made dramatic changes over 6 months and no one would have noticed except for industry insiders (including the type of people who read Hacker News). Instead, he wanted to reinvent Twitter in less than 6 weeks. This was a mistake, plain and simple. His actions came across as erratic, he made advertisers nervous, and as he has complained "Twitter has taken a huge revenue hit." But this will probably be temporary. In 6 months all of the advertisers will have returned.
pro:
It's likely that in 6 months advertising with be back to pre-Musk levels, but the staffing will be down at least 80%, so profits will be much higher than ever before.