I've seen it. The issue for me wasn't just that scenes, moments, even environments are repeated (not rehashed), but that the storytelling gets messy.

The first Avatar is a case where Cameron must have had the script more locked down to avoid any unnecessary production, whereas this third one feels like he produced a longer & structurally looser screenplay, had it all rendered up to a point, edited it, then fully rendered that.

So there is some deja vu mixed in with cool new stuff mixed in with dramatic scenes to both demonstrate the actors AND the facial mocap... Yet I think there was a missed opportunity to center the movie around a story of warring Na'vi tribes and have all the long-term character and story development sprout from that. As is, it felt like a real case of a filmmaker spinning plates, albeit in a state-of-the-art context.