"I don't know it's seems too me that it's popular wisdom that you learn most easily in your younger years but is that actually true? It seems to me that if you look at who is doing the most intellectually strenuous and demanding intellectual work in the country at any given time it's people in their 20s-50s who are doing university level research. These people are publishing papers throughout their lives and not just learning new things but developing new ideas.

Seems to me more likely that younger people learn better simply because they are more likely to have financial support and emotional stability from their parents/family/coach therefore they can dedicate themselves to learning in a way a 30 year old probably can't. BUT crucially if the 30 year old had the means to live like a 15year old I doubt he would be any less capable of learning.
"