>>149813961
It was more about Dark Phoenix Saga having defined most of the tropes for a cape comic heroine going bad, and John Byrne and Chris Claremont having very different ideas of what they wanted to do when they were both working on X-Men. This led to Byrne doing two more attempts at having a classic Marvel heroine go bad so he could do it all his way with no Claremont. First on FF he did Sue becoming Malice, then on West Coast Avengers he turned Wanda bad and quit mid-story.