The management class does not want this Twitter ordeal (likely a huge public failure) making engineers think their skills give them power over companies.
In a month they're going to say "look! we didn't have a single outage during the World Cup" and act like it vindicates their approach.
On top of that, it feels like classic "magical" thinking by a manager who doesn't understand technical scope or split responsibilities. Why bother to understand why you've hired so many people before blithely opining that 4/5ths of them are fireable? Who the hell wants to work for someone who says things like that? Certainly not the "high-quality" engineers who are supposedly being separated from the chaff.
"It's just money" says Elon and if his goal were to be the world's most massive troll (which I suspect is a large part of it), then it's achievement accomplished, full stop.