Whether Avatar 2 is called a massive success, versus if it actually is will be the thing to pay attention to.
There's a narrative around the prequels, that fans of the originals didn't like them because they were for kids, failing to ignore the originals were for kids. It's got some truth to it, but not entirely true.
I think Star Wars, especially now has to try and cater for people who are adults and grew up on it. While shows like The Mandolorian can strike a balance. They need to sort out what section of the audience's new material is for.
What is for everyone, what should be more for kids, and what should be more for adults.
I think when they don't, it's easy to fall back on, it's for kids also, it doesn't matter, space wizards, anything can happen, it's magic!
Just look at Obi-Wan, the audience for that should have been the kids who grew up on the prequels and are now adults. It had some serious themes, but it got ruined by being childish rubbish at times, where the writing and direction didn't matter.