This image https://imgur.com/a/2Rzeac2 in section "Fundraising, growth, and dilution" really says a lot! Person #4 in the company likely is as important as first 3, and took as much risk (also quit previous job and did not take a high-paying one at G/M/A/F), but ends up with 1/10 the share of the first 3 at best (options pool is spread between him and others).
I imagine person 4 comes in after an year or two after first 3 founders busted their arse to build a product to have the first few paying customers.
Before joining any company, you have to realize the opportunity cost. You could work at AAMG and make decent money being part of ~1 trillion companies. OR you choose to join a small startup that has managed to find a product market fit and now needs to scale to realize their potential and ride that wave.
In more sane parts of the world perhaps. In Silicon Valley, with VC funding, a year after company ia created, it is probably 50 people or more in size.
