I fail to see how the term layering does not mean anything at all. What I see here is a general consensus that it is a broad term which helps us identify a topic for discussion.

So what if it is a ubiquitous word. Karate became a ubiquitous term, yet "we" did not throw it away.

Vehicle is a ubiquitous word which can mean anything from an automobile to a spoon (as in "a spoon is a vehicle to get food into my mouth") and yet we do not say that using that word or talking about it is B.S.

The concept of "lots of light layers" vs. "one or few heavy layers" is certainly never going to be settled for all of mankind, since YMMV applies to this topic just like it does to anything else.