The disappearance of ME/CFS

In an unexpected twist, one of my best friends has (sadly) just been diagnosed with "Long Covid/ME/CFS" by none other than...The Bristol ME Service!!! The OT (not one I know) who diagnosed my friend said that it's "essentially the same thing and an acute Covid infection was clearly the trigger". Paradoxically, they then said (like the letter) that one of the main differences is that they expect the Long Covid cohort to recover whereas ME/CFS is expected to be a lifelong condition. Even my friend shrugged his shoulders at that.