I'm in my early 50s with a career spanning three decades, worked in fintech, worked in various FAANGs, lived in SV for close to 10 years, lived in NYC for half as long, now semi-retired.

For someone young (early to mid 20s), I agree with what you wrote. Being really, really good and actually enjoying doing it, should be a must.

For someone of your age or older, I see a lot more risk. If you start from zero, it will take you at least 5 years to build up ammunition (a degree from a good university and some demonstrable experience) that's going to open the doors that you need open and give you a shot at passing the entrance tests. And then the "being really, really good" part comes in except you're now 5 years older facing fierce competition and there's no guarantee that you will succeed (who knows what the market will be in 5-10 years, the trajectory doesn't look promising).

Personally, I wouldn't do it. The skills needed to offset the risk are hard to acquire in the timespans we're talking about, unless you're truly exceptional. But offseting the risk for me means living in the US and working at one of the FAANGs (job security and very high total compensation). Others see it differently.