Correct, the term always has been meaningless except in contexts where there is a mutually agreed on *verbal* definition of it. Whenever it appears in polemics, bourgeois or marxist, in the context of arguing that a given position ir activity of *some human* is "unnatural" in contrast to the "natural" position or activity of *some other human* it serves only to sow endless confusion. *Never* use it in a context in which disagreement over its meaning exists. "Ecology" should probably also be used in a "neutral" or technical sense. Then one can argue whether a given set of ecological relations are destructive, constructive, or irrelevant. As a polemical term (positive or negative) it clearly only creates confusion.
This debate is moving in a positive direction: a debate grounded on the assumption that all parties of it (a) hold fundamental positions in common and (b) are operating in good faith. Use of such blank checks as "ecology" or "natural" as polemical terms can destroy those foundations.
The core meaning of "nature" in any context has to be, "what is."
Carrol