The dumbass scene with Rhaenyra isn't Alicent's liberation arc; it's simply a shift in who holds her reins. Instead of men, it's Rhaenyra now.
Alicent's true liberation arc should have happened in S1 when she was actively beefing with everyone around her; she was plotting to have Rhaenyra’s treason acknowledged, scheming to outmaneuver Otto, and was not afraid to defy Viserys' wishes.
All of this culminated in the confrontation at Driftmark. That should have been the moment of Alicent's liberation—the point where her worst fears come to life, proving her right; Rhaenyra’s flaunting of her duty finally led to Alicent and her loved ones bearing the consequences.
Viserys, in the same breath as he coddled and protected Rhaenyra, demanded that Alicent let go of her grievances and make peace with the injustices she had endured. At that moment, Alicent realized she deserved better, so she snatched Viserys precious dagger and tried to stab the very woman he ordered her to reconcile with—the same woman who, moments earlier, had demanded that her son be tortured.
Alicent stabbing Rhaenyra should have been the ultimate rejection of Viserys—a moment where she finally broke free from his shackles. That should have been Alicent final stance against her jailor. Alicent refusing to bow to his demands, and is finally free to seek justice for herself.
This should have been Alicent's liberation arc.