It might take a few episodes but she wouldn't be one of the main girls if a end game romance wasn't on the table with her eventually.
I can't imagine her not being a romance option towards the end, but I do feel like DPC is gonna throw us a curveball with her and a lot of people will cry. I like Sage a lot (after all her and Riona make up my S-Tier) but if the curveball happens I'm happy to go for a new playthrough dedicated to her. She's worth it.
The curveball being:
Pretty sure the other main LIs will stick to their path, so Isabella will be CHICK-Neutral, and Maya, Josy and Jill will be mostly CHICK and the one and only DIK-Path main LI I think will eventually also drop out of DIK and into prefering you when you're more CHICK/Neutral.
DPC just gave her an excuse for having been into DIKs since she hated the idea of emotionally opening up cause her family never did that in the past. Guess this is also why her and Chad were together despite Chad seemingly not being interested in her anymore and Sage also just wanting to know who Chad is sleeping with and not actually fighting to keep him, cause she probably also doesn't care about him. You're basically just making her realize she doesn't need to put up a front and care about appearances and she can just discuss feelings, clear the air and be done with it.
So you'll basically be stuck in a situation where if you started as CHICK/Neutral you never really get close to Sage and you're fucked. If you started DIK and then kept going full DIK, then she initially likes you but since you eventually get stuck in "permanent DIK" mode she will probably develop into a person that realizes she doesn't actually like some of the shit a Massive DIK MC will pull. So your road to glory will be something like starting out as DIK and then steering more and more towards CHICK so you eventually end on Neutral where the Sage Path will succeed.
Kinda sucks that this would mean 0 of the 5 main LIs will be for the DIK MC in the end, but then again the DIK path makes up with it with sheer volume, sleeping with pretty much all HOTs and the Strippers.