@bermuda8
Yes, I was quite struck by that terminology as well!
There are indeed many other takes on the variable symptoms, never mind the etiology, of LC/CFS/ME, e.g. chronic inflammation, overactive immune response, reactivated latent viruses, etc.
It's so disappointing that after DECADES of research we have nothing definitive.
Me, I will patiently await the two year mark upcoming in about eight months, following my single bout of Covid, hoping that this lifts as it did when I first had it in the late 80s.
In the meantime, I will indeed continue to get boosters, as I feel more threatened by catching the virus again, as compared to being vaccinated, to which I don't particularly react. But individuals do vary, so I respect that.

And I feel as well that we can't figure this illness out because the UFO denizens don't WANT us to figure it out!