Story time: in 2000 my first manager at Microsoft had not one, but three houses on Lake Washington, a small stable of fancy sports cars, and a rather substantial boat. In 2002 he had none of those things and was bankrupt. Moral of the story: diversify the living shit out of overheated stocks.
I have to imagine that Meta, and other big companies are in a similar situation. Meta, in particular, gives beefy grants and anyone that joined 4-5 years ago has seen the stock go up 7X. For a senior Engineer that held on to the initial grant and refreshers, that stock would be worth $5-10+ million now.