11. Stargate Reboot
The Movie: In late 2013, original Stargate director Roland Emmerich stated that he and MGM were busy working on a reboot movie, which would kickstart a new trilogy of films. By 2014, Warner Bros. were set to help distribute the film and all the key creative players seemed to be in place.
Why It Got Cancelled: Producer Dean Devlin declared the film cancelled late last year without much elaboration, though many speculated at the time that Independence Day: Resurgence's disappointing box office was most likely to blame.
Considering how nobody outside of those directly working on the Stargate reboot actually wanted it to exist, it's fair to say that the Independence Day sequel actually did something useful.