Gains from pretty much all "advanced" techniques are incremental. Most improvements - whether cars, sports, business, marketing, etc. - come from mastering the basics.
Well sometimes yeah, but I can state without reserve that when I tried a different set of strings - Ernie Ball Cobalt vs. the Slinky, I actually could hear a significant difference. Same goes for changing pick thickness. I think it's important to note that it's really only at the top % where improvements become kind of logarithmic / incremental. 10,000 hours is kind of just a start with guitar.