You're probably in the majority here actually...and I find that to be a bit (or more) of a gross oversimplification. Very 20th Century thinking, the rush to close the door and have a soundbite.
I think he was disenchanted with the state of the world in general more than anything about Coltrane. I don't think he was that myopic about his life.
After his last return, he played almost 50 years uninterrupted. That's hardly "adrift". And between the records and the bootlegs, there is more than a little great playing to be had. There's also plenty of unsatisfying work as well, but "adrift" is in no way accurate.
Time for a new narrative, one based on specifics instead of hasty, overly simplified generalizations.