I think that was because it was some made for TV thing that was switched to movie and people thought it was going to just be a D+ show.It’s easy to say something was doomed from the start in hindsight. Plus we don’t actually know how it’s going to do. People were very pessimistic about the Moana sequel when that was first announced, yet all signs now point to a blockbuster.
I think once that was cleared up people where excited for Moana.