Why don't you just work at one or two big company and get your FOMO out of the way? The worse case is you make more money (hopefully?) and hate it but you never need to look back, while your best case is a much higher ceiling.

You're 30 years old, assuming you work for another 30 doing 1-2 years at 1 or 2 big corp isn't much.

I mean from my personal experience, it's really the team within the big corp that you work at that matters. The big corp can try to drive a cultural and larger goals but that the end of the day it's your manager and peers that has the most say in your work and happiness so if you're interviewing, I'd really focus on getting to know your peers, manager an if you get a chance, your manager's manager (director title, most likely)

I'd never say the experience at 1 startup would be the same as another - so why people are saying you'll have the same experience at 1 big corp compared to another, or even a team within the same big corp...is beyond me.