A. B.
The other threat needed to be established in that first film. Revealing a new antagonist later on doesn’t work, such as Palpatine in Rise of Skywalker.
C. D.
Goes against The Force Awakens.
E. Goes against The Force Awakens and introduces another antagonist force in an already convoluted and confusing sociopolitical world that wasn’t fleshed out as it was.
Again, your beef with that choice should be aimed at Abrams.