Andy Carr’s review published on Letterboxd:
Trades in the first Avatar's lean and unoriginal plot for, essentially, no plot at all!
A sensible narrative direction up-front gives the movie good starting momentum, but Cameron quickly abandons that plot in favor of 90 minutes of meandering worldbuilding and mild character development. It's all capped off with a stunning action climax that's pretty cool until you realize it has nothing to do with the initial premise. The film's final moments leave you thinking, "THIS is the note he wants to leave us on, with three more of these in the chamber?"
The new locales, wildlife, and VFX are outstanding when they aren't marred by Cameron's futzing about with the framerate (edit: only an issue in 3D; watch in 2D instead). If the action had been more plentiful, and the climax more tied to the first act, this may have actually outdone its predecessor.
Having slept on it, its messiness is what sticks with me, far more than the sparing moments of gorgeous action or the meager bits of character. Largely, The Way of Water is more of the same, with a few improvements and some new setbacks. I had a good enough time, but I'm in no rush to see more of these.
RIP James Cameron; he's not dead, but he's already set up shop on the hill he plans to die on.
Full review here.