To play devils advocate, most people who intentionally optimize their career focusing on equity rather than TC know this fairly well and have had their fair share of duds. You can also make the argument that overall the EV of optimizing your career for equity is probably lower than just getting a high paying FAANG job.
However, with all that being said, the only way to be the "overnight millionaire" is to play the game. Also, there really isn't any overnight millionaires, those people probably worked for years for sub-par comp compared to alternatives and took a large risk whether knowingly or not to get that payout which may or may not have existed.
There really is no free-lunch if your employee #5 at Uber you made tens of millions of dollars, however you took the risk of being employee #5 at Uber. Look at Snapchat though they paid huge amounts of equity when they were trading in the 10's even after they IPO'd if you were employee #10002 and joined Snap at 100k-250k in equity that netted you anywhere between 600k-1.5m if you held the shares, that's not including cash comp. However, you took the risk of joining a tech company that at the time nobody really wanted to join and may very well have closed the doors.
That being said there very much is an alternative risk of going the safe route of just optimizing total TC. That risk is generally that path is well defined, the salary bands are well published, and overall despite whatever amount of effort you put in that will be around the amount you make. You'll be flogged into a corporate grind if you really want to make more either by job hopping or trying to get promoted. The risk with the defined path is well, its just that linear and well defined, not saying it's a great path and maybe even a better one overall but it means you'll be working for Facebook when the next company that is going to disrupt Facebook is potentially out there today.
Equity stakes for employees means the tails on the right side of the distribution are rich. Assuming you get a cash comp that makes you happy that equity stake my very well be the thing that puts you in the 1-10m+ range if your extremely lucky. If not even if its mildly successful a 50-500k payout with a decent salary of say 150k a year over 5 years netted you 160-250k comp a year while putting you in the run to make potentially millions.
If you work for a "startup" that is a decent place to work and respects WLB etc then taking those "risks" over your career might make a-lot of sense. You'll probably learn way more too, have more autonomy, and frankly they can just be alot of fun.