I agree, the original avatar didn't have a particularly good story. The lead actor was very boring. He was in the Terminator Salvation movie and his career didn't really happen after AVATAR. I saw the film opening day in 3D and don't remember much about it except I didn't really like the aliens very much. The visuals were great though.
They already filmed up to Avatar 4. (out of 5). I can't help think that this huge, billion dollar project would turn out to be one of the biggest failures ever. The film industry never recovered since COVID-19 (which was why the release of Avatar 2 was delayed for 2 years). 3-D never really took off. It seems to me that Cameron's talent could have been used in a few more interesting films than this.
Kind of reminds me of Cyberpunk, which was the most expensive game of all time. Cyberpunk 2077 is getting a sequel too, due to making a huge profit despite the downsides and reputational damage.