Actually, you certainly can do that. Most people do. And depending on what you're optimizing for, it seems pretty rational to me.

Another stat for you: most entrepreneurs fail "about twice" before making it, i.e. you'll probably fail 1-3 times for sure before entering the 5% of those who create a profitable business. Trick #1, thus: you can roll the dice several times (consider 2-5 years per "real try").

Yes, but that's for founders, not employees. If "success" here is defined as "made more in risk-adjusted income as early-stage startup employee than I would have made as big tech company employee", I doubt any early stage employees are "successful". Every failed startup you participate in (2-5 years of your life gone) adds to the opportunity cost "debt" you have to make up once one succeeds.