Avatar remains insanely popular at Animal Kingdom and a strong force in merchandising for that park. You see kids and adults with Navi tails, headbands, ears, and shoulder banshees pretty often in Florida. People love Avatar in Florida, and based on what I’ve seen I’d assume Disney would want to bring that love to California given how they try to push Figment and Orange Bird merchandise here, and Duffy and Gang in the domestic parks. Also suggested it as Avatar is set in the future and Nemo was set in the early 2000’s.
At the same time how often have you seen a kid pull up as Crush or Nemo in a giant fish costume?