I was at my best (on electric guitar anyway) about 30 years ago. . .before I got old and just about forgot how to play.
But I'm slowly getting my chops back.
Incidentally, the only degenerative disease I have is arthritis in my back, and I'm hoping it doesn't get much worse if any. (I'm prepared to get super skinny if I have to!) But I have a good friend who had MS and it actually went into remission--something that almost never happens with MS. Just saying that you never know what the future will hold. Well, except death and taxes. . .and crooks running the world, but that's a given.