I've also managed to hit with some former college guys who made top 500 ATP. they are insanely good with hard serves and insanely accurate ground strokes. the difference between those guys and a top level player is night and day...scary how good top athletes really are.
Also several years ago played in a pickup soccer game with a guy who washed out of Manchester United's academy as a 14 year old. In that same pickup game were guys who at the time were playing D1 soccer, and a few had spent time in MLS academies. The ex-United guy was lightyears ahead of everyone else despite having been out of the game for nearly 10 years and having a bad knee. The guys who make it to the top are utterly incomprehensible for a layman to understand.
It's just like how if you're playing a GM in chess, and you might be a decent enough player yourself, you won't even sniff a chance of doing well much less winning. Those same GMs turn around and get effortlessly destroyed by Carlsen or other top players. It's just a different level that us civilians cannot fathom.