But then there's the career of his running buddy Al Cohn, who was very good in the '50s and '60s and then just got better and better and stronger and stronger, at times almost amazingly so (especially rhythmically), right up until the very end and without undergoing any profound stylistic change or absorbing any "advanced" influences. Thus it's not like I'm holding Zoot up to some imaginary or elitist standard.
Different lives. Cohn parlayed all that studio work into a business & ended up doing quite well writing chats for shows and revelries and follies and dollies and all that stuff. Accepted and succeeded "non-jazz" challenges, so the playing itself, when he did it, wasn't his daily grind.
Zoot kept on being Zoot, taking Zoot gigs. I'm sure he did well, but people who drink a lot and never really variate their world usually end up being the part of the toothpaste that never makes it out of the tube, even after you start rolling & squeezing the last bits out.
I'm all for personal introversion and isolation, but only if you can do it without letting it keep you in the tube until the time comes for the tube to get tossed in the trash.