There's a big difference between stock options and RSUs. Nobody became millionaires off RSUs unless they started at Tesla <2018. I'm not convinced everyone at Tesla is offered options.
Take this as the heresay as it is, but pretty much everybody at Tesla gets at least $20K in RSU's. If you got that pre-IPO and kept it this long it's worth more than a million. But even if it doesn't appreciate at all, over 4 years that's a similar payout to the MB payout referenced in the article.