I wouldn't call it metabolic if parts were missing or otherwise had communication malfunctions without any issue in acquiring/using energy itself.

But I'm sure lots of things go wrong when the brain doesn't get the energy it needs and is forced to compensate.

Even more to the point: If something generalizes without a qualifier like most/many/some/can be, there might be an implicit "all/every" (or careless communication) and that makes it all suspect.