[LeicesterCity]

At ages 10-20 one has the time to go deep into many different subjects, would that be viable for someone late into the game (20-30s)? Or would they have to narrow the number of subjects they explore?

[robertk]

Learning is age invariant. The difference is you will have a day job, but yes, it’s viable.

[tonyedgecombe]

That statement is a bit of an oxymoron, you can't go deep into lots of subjects. You pick one and immerse yourself in it or you cover a wide range to a shallower depth.