Eh.
Sage is/was my main girl since season 2 when I switched off Maya (who had become unbearable by that point), but I kind of agree with people being disappointed in her last few episodes. I'm not sure DPC knows what he wants to do with her, and frankly, I've said it before a good portion of her dialogue and Quinn's feels like it ought to be flipped. Instead of adding depth to the character, the constant back and forth between super wild slut and deeply emotional girl (with a healthy sex drive) is starting to give me whiplash. Which Sage am I going to get today?
It's not about the quality of the sex. Frankly, the sex scenes in BaD are extremely well made, but I care so much about the characters, its much harder to objectify them. Which is great. But it also creates a problem with a work like this that is more than just porno. This isn't the only character to have this problem either. Different girls jump personalities from scene to scene rather than slowly growing or deepening.
I think I understand what he was going for with Sage, he just did a shitty job of conveying it to the audience. Sage starts out as a 'slut' and then reforms to a good girlfriend in our mind. But that's not it. Sage is an adventurous girl (its one of the things I like best about her). She starts the story in a shitty relationship. But you don't save her from it. She rides it out, because of her own issues until it collapses and then you're there for her after. But Sage isn't turning into the good girl she was always meant to be. She's a hound and she's finally found the ideal partner to explore all her impulses with (you). She trusts you. She wants you. But she also wants you to help her discover all the things she would have felt shamed for for the past few years. (Chad guilted her over her high sex drive, remember?) From this context, the story makes a lot more sense.
But its delivered poorly, Sage shouldn't have opened up emotionally to the MC so soon. Instead she should have told him in Ep8 that she wants him to be a fuck buddy and nothing more.
Not only would this have made her distinct from all the other characters (sorely needed), but it would also have made it much much harder to choose her. Which gives the choice e more narrative weight. Down the line, she would open up more (the stuff we saw in season 2 and more still) climaxing (heheh) in her finally admitting that she WANTS to be in a real relationship with the MC.
I think it's time for DPC to admit some of his failings as an artist (which isn't to say he isn't amazing, but no one is good at everything). He writes good concepts and dialogue and decent plotting, but the man needs an editor. Someone who helps him smooth out arcs between scenes and keep characters consistent within their own voice.