With Avatar: The Way of Water's box office performance settling the question of whether or not there was an appetite for more Avatar after so many insisted that no one gave a shit about the sequel to the biggest movie of all time, I think it's worth asking: why are so many people so intent on doubting James Cameron? And not just doubting him but actively rooting against him? With Avatar, Cameron has created an entire world, a whole franchise, that is exclusively his own. He's a nerd who has the clout to write his own ticket. There isn't a single studio executive with the license to second guess him or strong arm him into going against his own instincts so why is every nerd not in his corner? You'd think they would be, right?
When it comes to Avatar, there's no aggressive subsection of fans that can attempt to drive the discourse about it. They can't say that Cameron isn't respecting the novels or the comics or the original trilogy or any of that. They have no ground to stand on. What's more, they also aren't ahead of the general public when it comes to Avatar and I think that gets nerds twisted up as well. Whether these nerds love or hate a new Marvel or DC or Star Wars movie or show, I believe they enjoy the satisfaction of being able to feel like their opinion is more valid because they're an OG fan. They feel like they can back up their bullshit by going into the lore and mythology in order to tell someone who enjoyed whatever the new thing is that, well, they're wrong about it. With Avatar, Cameron has taken that (imagined) advantage away from them. There's no way for them to feel superior to anyone when it comes to Avatar (except by trashing it).
The whole complaint about the original Avatar not leaving any "cultural footprint" and thereby failing to matter is about a certain sub-segment of nerds believing that unless they've adopted something, that unless it belongs to them first and everyone else second then it's not valid and they so they feel obliged to minimize it. Nerds are territorial and I believe they enjoy feeling that when it comes to pop culture, that is the one area in life where they actually have some significant clout, where things must naturally bend to them. Avatar, though, is a sci-fi property that belongs to everyone equally. Cameron doesn't have to go on stage and play to the crowd at conventions, hoping the fanbase won't turn against him. Nerds can't school anyone about whether the latest Avatar movie is faithful to the source material. Everyone is coming to these movies on the same level and that is a rare thing with sci-fi properties, especially now when nearly everything is a pre-existing legacy franchise.
One thing's for sure - whether they do or don't, it won't make a damn bit of difference to Cameron.