The most likely explanation is that your premise is wrong - top management of these companies is not low quality. Instead they are very good at their jobs, but what that means is just not be what you think it is.
My experience working in a small startup, a largish tech company and a FAANG, is that management (especially at the top) follows a highly unbalanced bimodal distribution - that is, about 85-95% of management has no idea what they're doing and in many cases are actively hurting the company. But 5-15% are actually great and know what they're doing, and can carry the deadweight along. But since they're a minority, they are completely focused on getting the business to work; the deadweights are the people making the open office decisions.
> The most likely explanation is that your premise is wrong
We have factual evidence about Meta overpaying 50% for talent due to poor work environment and of thousands of engineers complaining about this issue for a decade.
Poor management is conclusion, not a premise.
You need to bring counter-evidence for why this straightforward issue was not addressed 10 years ago.
Maybe overpaying 50% for talent is an OK price to pay for what they were actually trying to achieve. Engineers are fickle - they'll complain about one side of an equation while ignoring the other N sides.
Maybe cost was never an issue, but collaboration was. Maybe the culture that this policy generated was more important than the extra dollars they had to spend.
Or maybe, just maybe, your "factual evidence" is actually just a casual quip Joel Spolsky threw out there that one time for quick laughs. I would really love to see your sources that state "if Facebook had single offices instead of an open plan office, there would be just as much innovation, collaboration and successful products, yet the total cost of payroll would be 30% less." I'm pretty sure that's impossible to prove, regardless whether you'll label it with "factual evidence" or not.
They are generally out of touch with the people they manage, clueless about how to effectively help them, and they spend a lot of time posturing. So I guess... the job description fits that of a washed up politician?
Then there are the 5% of upper managers that know what they're doing. But to the rest it would be an insult if you asked them to 1-to-1 with a random employee and actually understand the real problems in the company.
Anyone feeling this is wrong is free to test it. Ask an upper manager in a large tech company to speak with your coworker who's frustrated at work. Maybe about RTO - there are many of those around now. Good luck!