Not Dylan or Sam, you don't play Aiden too. It really restricts the content you get to play.
Though I know you play the lesbian route and even I enjoy it a lot more than the hetero route.
Also I feel Sophia is safer in that route and the women are not a direct replacement of Liam, they are an addition, more like a bonus for Sophia.
While, yes, it does restrict the content, as I've said before, there really isn't anything on those routes that I can't get on the routes I
do play. The only real issue is that after 6 months wait, I got 10 minutes of rather bland content. And after this update it's likely to be around 2 years wait for 10 minutes of rather bland content. Playable day 12 for me is going to just be Sophia waking up, then a few renders for the class, the salon visit and that's pretty much it.
And yes, if Sophia was to ever get caught sleeping with another woman, Liam has already shown he's not opposed to the idea - he's already suggested a threesome with Nathalie. Might raise an eyebrow if he catches her with Ellie and/or Patricia, but I don't think it would be a complete dealbreaker like it would with Sam, Dylan, Aiden etc.