Most of the people I know who have joined startups early could have, or did have, FAANG offers, or finance, or anyway something with bigger comp at the same tim

Most of the people I know who have joined startups early could have, or did have, FAANG offers, or finance, or anyway something with bigger comp at the same time. I admit to sample bias here, somewhat unavoidable. I would say the defining feature of most (the others had experience hating big corp life) the people who chose the startup is that they cared more about what the startup was trying to do than the paycheck. It's a harder decision to make now than it was in 1998, but in some ways it's the same decision. I have to disagree with the mentorship aspect of OP - that isn't inherent, that's a choice, and companies of all sizes choose to do it poorly. Full disclosure - if I were counseling a wet-behind-the-ears developer today I'd probably encourage them to try FAANG life for a little (assuming they could); worst case is you learn some useful stuff and get a nice nest egg.