The look-at-this-crazy-revenue-faucet period resulted in a LOT of constant hiring for a solid decade. That's not the way towards an efficient org.

So even if they fuck over 70% of their expeienced staff and are left with a relative skeleton crew, they'll likely be able to keep the lights on and keep the advertising-revenue-faucet running for years.

And... given that they've mostly failed to break much of any new ground despite all the previous hiring, the rest of the world probably won't care.

(Plus, as the article itself notes, Meta has long had a pretty toxic perf-review culture; speculation about if that has to do with the lack of any particularly noteworthy new products/features/etc is left to the reader ;) )