Sure, but there is no way to diagnose it. Is it a mental affliction like allergy to electric devices some claim to have and which feels very real to those people? Ephedrine does affect some reward chemicals so there can be some withdrawal effects. But so does caffeine. Doesn't necessarily mean your adrenals are burned out.
What some call adrenal exhaustion might just be depression for whatever reason. Depression can make you exhausted and ultra sensitive to any bodily sensations.
I agree with what you're saying.
We can't diagnose it. Not being able to diagnose something doesn't preclude it from being "real" in some ways.
For what it's worth, I think it's a string of bad things going together -- high stress, low nutrition food, tons of caffeine, sleep disturbances. That's probably the majority of the population and now you can sprinkle in cigarettes, drugs (Rx or rec), alcohol, pollutants from work or environment, people living off Flint water, etc etc.
Do we really think these things won't have an effect over time? Beau Baisden didn't die from a year of doing roids, but after a decade he sure put himself in a nice deep pile of shit!