I understand its too late in the process to change this for Avengers Campus, but I think they'll find that they won't do this again. Its really mind boggling not opening your land fully. Even new Fantasyland didn't open with Seven Dwarf Mine Train if I recall correctly.
My main issue with Disney right now as a consumer is I don't really "trust" them. When they announce a project I have virtually no excitement anymore. Constantly promising you the world then failing to deliver on all ends with the final product. The lack of entertainment in SWGE is just appalling. Universal I'm sure has done this in the past too, but at least when they announce whats coming, it actually is what comes in the final product. Imagine if Uni announced Hagrid's and all their magical creatures, then we only get the Centaur and the Pixies. Thats what it feels like Disney is constantly doing now and it feels way too manipulative to me.