I brought up that it seemed reminiscent of Chronic Lyme's disease, and he said that yes, that's also a very questionable diagnosis.
I didn't really get into the weeds of that discussion, but it kinda put me off, since I have had several friends over the years who have had a hard time convincing the medical establishment that they have a real condition. Things like Chronic Fatigue, Ehlers-Danlos, Lyme's as mentioned, etc.
There's this historical view that since it is mainly self-diagnosed women affected by all these, it's just a case of "women complaining" or somesuch (maybe not stated so directly) and not a real condition or mostly psychological.
It gets dismissed, so it gets less research. Since it gets less research, doctors can say "there's not strong evidence to support it," and so the cycle continues. There's some sexism (and other -isms) inherent in the system, I do believe.
It's entirely possible that women, for biological reasons, could be more susceptible to these system-wide hard-to-pin-down chronic issues. I really don't know; I wish there was more research being done.
But it was just a weird moment where I got to witness that dismissiveness firsthand, from someone who otherwise I generally respect.