I believe in the starting age-theory. I started playing the electrical guitar at 11, and today I can play whatever tune I want. I would be at the IM level of guitar playing, so to speak. The 99th percentile.
As a contrast I started to play chess much later, and that was casual leisure chess. I guess that I could improve with a proper training regime, but could I reach a rating of 2000 ELO/2100 USCF ? Hmm...
the pivotal question remains:
do you really LIKE chess?
ME: That's really what I was getting at.