Agree! In my opinion your 20's should be for studying and exploring things on a higher level (university, etc.), your 30's for starting building your "systems" and master something so that in your 40's you should be well equipped to do real innovation.
Of course, some people may be faster and some slower..
And of those who was a real inventor or innovator? I'm not talking about business innovation, but real and durable innovations.. After 100+ years of being invented, I still ride my bike every week, but I highly doubt that Amazon as shop, MSDOS, Google as search engine or Facebook will be used in 2200!