For founders I don't think the calculus has changed much. You do it because you believe in it and have the stomach or resources to take the risk. For workers it has changed a bit from 10 years ago. I just call this making hay while the sun shines - I don't think the massive salaries at FAANG will last forever.
If you are a founder who takes on investments, the only thing “you believe in” is an exit strategy. Don’t drink the kool aid. Most founders are not trying to feed starving children.
Whatever your purpose, you believe in it, whether thats this is a business plan that will make me a bunch of money, or it'll make an impact, you still gotta believe.