"Man reaches the maturity of his reasoning and mental faculties scarcely before he is eight-and-twenty"
The vast, vast majority of people at age 20 are playing videogames, jerking off, and doing the bare minimum to get by. Even if you 'peak' at 20, it means fuck all because of this. Let's say at 20 you're at 100%, then you lose 1% per year (not a good model). So you're at 90% at 30. But your work ethic is fucking 5% at 20, and 100% at 30. So I think the absolute, final and end cutoff for getting meaningfully good at something is probably around 50-55, and later if we get moderate life extension to lifespans of 100, 110, 120 (or just sharper mental acuity into old age)
Essentially, don't worry about it, since you sure as fuck can't control it. Here's another way to look at it: say you're 30, and you have to start from behind if you go into a hard science / technical field / whatever it is. Assuming the pessimistic view that you will never be as good as someone who started at 10 or 20, you have two options: do it anyway, be 80% of the scientist/engineer/programmer/whatever the fuck the person who started earlier is, and still make good money and enjoy your work. Or don't do it, be 0% of what they are, and work some shitty slave job with 0 prospects no matter how good/bad you are. The choice is simple
