Not OP and never worked at Meta, but according to Sarah Wynn Williams’ Careless People, the incentive is not so much the pay, it is the options. If you get in and leave before x number of years or get fired (not 100% sure how it works) you will lose the golden ”never having to work again” -ticket. Apparently it keeps people pretty meek and helps silence the jiminy Cricket in the backgrpund.

Not really how it works anymore. Everyone just gets 4 year RSU grants with an even vesting schedule and no lockout period, and it has been that way for a long time now. I've never really heard of anyone at Meta getting options (maybe possible for execs?).

That said, with enough stock growth, the stacking RSU grants can still enter into "never having to work again" territory depending on your role/level and how many grants you've been able to stack.