As I saw pointed out elsewhere, with a headcount of only engineers and these alleged 10 managers per engineers, this would leave twitter with like 630 engineers and 6300 managers which is a clearly a drastic underestimation of the number of engineers and that's before you count roles like sales, support, etc.
Sure, but that team may have N engineers and those VPs may have N teams, so that doesn't seem so ludicrous for a 7000 person company. Or even 3500 person company by EOD. Certainly in my company there's about a 200:1 engineer:VP engineering ratio, so pointing out every engineer reports to a VP is kind of a meaningless statement
And there are also finance people, HR people, sales, etc. people. The company is far from entirely engineers, their managers, and the managers of their managers.
Don't take everything Elon tweets at face value