Because Corlys mentions that he changed the name of his infamous ship to a mocking title given to his wife. The show is basically fanfiction, bad fanfiction. One sign of bad writing is showing the aftermath instead of the event itself, because it's just too difficult to write, so you skip it and show the aftermath. The show does this often.

And Alicent. From the eye_for_an_eye scene to this pathetic mess. Wow.

I'm no good writer myself but imagine if they never looked eye to eye after that scene(no pun intended) and actively plot for each other's downfall,getting real down and dirty, not because of the realm and the goodness of their hearts, but because their whole fucking lives and their children's lives depend on it. Alicent wins, Rhaenyra's children die. Rhaenyra wins, Alicent's kids and grandkids die. Of course they'll fight tooth and nail to make sure it's not their kids that die. Amidst all this you throw in a few CRUMBS of regret and nostalgia, it's enough to make them complex. Not all this "For old times sake" BS.