I really don’t see how it does that at all. Book Alicent is pretty much a power-hungry villain like her father. Sure, she had more of an active part planning to crown Aegon, but it’s a pretty thin characterization for a multi-season show. This Alicent has been used as a pawn, lied to and manipulated by her father, and still manages to create her own loyal faction among the Greens (by taking advantage of Cole’s hate for Rhaenyra and using Larys’s creepiness to her advantage), schemes to see her preferred outcomes come to fruition over Otto’s, and has her own complex relationship with Rhaenyra that isn’t just cartoon animosity. Her agency hasn’t been taken away, she’s just been shown not to be in lockstep with her father. It will add drama to the politics of the Green side in future seasons, so I like it.

I also imagine that we’re going to watch Alicent harden, become more ruthless as the show continues— much in the same way Rhaenyra certainly will. This makes their characters deeper by showing us the journey they take instead of giving them fixed personalities from the beginning of the conflict.