Avator is a odd film. It was the highest grossing film of all time yet after it left the box office it just died. No one cared about it anymore. They had Halloween costumes for it that year then after that no one dresses up in them. Star wars, Beetlejuice, ghostbusters and others still have costumes every year. The toys died and so did the video games. It's biggest thing right now is a ride at Disneyworld!
Harry potter is over 20 years old but has two parks areas, toys, video games, legos, shirts, clothes, books and movies. Avator has a new movie and a cool ride at Disney and that's it.
Also ask anyone on the street to name someone from avengers, or star wars or ET and they can tell you. Even rose and jack from titanic are still known. Can anyone on the street even name anyone from avator? It just was gone and forgot just like that!
The trouble is it's big claim of fame was 3-D and it's cool cg. The plot was a rip-off of dances with wolfs and ferngully so nothing there. It was the 3D craze. Alice came out right after and also did well.
Alice 2 came out and bombed. Why? 3-D craze is over!
I'm sure it will do well but it will never be as big as the first unless the plot is incredible and they make some new gimmick like 3-D without glasses. It might make a billion but without a gimmick I doubt it will make endgame numbers.