Most are probably on their 30s and 40s, especially those with prior interests in cryptography and a digital cash system (Nick Szabo, Hal Finney and others, just to name a few). While the majority of those with interests in crypto are in their 20s, it's undeniable that those whales are somewhat older, due to their money and experience in the field. It'll be cool to know the demographics of bitcoin users but then again, that goes against 'privacy' and some statistics regarding age groups of bitcoin users may somewhat be unreliable.
I agree with you that although young people accept crypto more than middle-aged/older people, more of crypto's whale-level holders may be 30-40 years old, they have more financial Experience, having more money available for investment, actually dominates this market.
Yes because bitcoin and other crypto currency are the invention of modern age but the old people cannot easily get the idea behind it. Holders are mostly young as they have more patience than those who are older. So I think making an old limit is not fair but actually just because of generations gap it takes time to make them understand.