One reason that “Classics” achieve that status is that they are wide-reaching and timeless. Some of the theories that were applied to the book at the turn of the 19th-20th Century can be applied today – more than 100 years later.
There really was a good reason to take those piano lessons as a child. Seriously, though, I find that, when I’m involved in an intense project, or have been focusing too much on something, a 10-15 minute break on an instrument really helps loosen the thought processes. Now we know why.
FYI – it’s never too late to pick up an instrument. I started piano at 7, guitar at 40, and violin about 5 years ago.