Even if you consider the group mind element of Pandora's ecology plausible (which I don't), it doesn't change the fact that it's extremely similar to idealized, fantasy views of nature. It is in narrative terms the same thing just couched in slightly different language.
ALL stories have to have narrative terms that are relatable to the reader. Science fiction uses fact and extrapolation of fact as it's narrative term. Fantasy invokes "magic".
While functionally they may serve similar purpose, it is an abuse of the term "the same", IMO to use it to equate the two genres.
It's possible. I personally think with Avatar the alien society has little interest evolving beyond the tribal level because they live in a magical equilibrium. How the ecology operates, complete with the world-net implications of Eywa, doesn't require for the Na'vi to improve their lot with technology. It's extolling the virtue of a static, harmonious society, as opposed to the progressive (and thoughtlessly destructive and reflexively imperial) world of humanity.
I would submit that it is a natural
not "mysitcal" equillibrium, just as the human body operates in a natural equillibrium of it's own. In this case, functionally, the human presence would be akin to an invasive virus or dangerous bacterium. When said virus/bacterium became an active threat to the equilibrium of the planet, the planet's natural response was to rally it's "anti-bodies" (the Na'vi and fauna) to fight the threat (a concept that was also at least contemplated in the Trek episode "The Immunity Syndrome").
I think the real issue and thing to watch for in the Avatar sequel will be to see just how robust the Pandoran equillibrium is. Will things return to the status quo absent the human presence, or will Pandora have to "evolve" to meet the challenge of changed circumstances?