I want to hear from slutty-version Holly about her experiences. She's weirdly passive in just going along with obviously-a-bit-creepy Ivy all the time on that path and if she's clever enough to be writing and quite introverted she'd definitely have thoughts and it's weird she never says anything about this massive lifestyle change. Plus Robert's an idiot and she'd notice, even if she liked the sex
A sluttier Holly was weirdly passive during Ian's half of the chapter, but that can be attributed to only really knowing and being interested in Ian. Likely an Ian that had already ignored her (big fuck you vibes most of their scenes together), until Lena arrives. Additionally, this version of Holly is browsing social media far more, and probably (s)texting Robert, Mark, and/or Clark, and definitely keeping in touch with Ivy; which will also take her attention away from the group.
I think for Lena's half, we'll get a lot more discussion out of Holly, as they both have a connection with Ivy. Lena will certainly want to discuss with Holly all of those texts she sent to Ivy, regardless of if Lena is slutty or not. And they're the most likely roommate pairing on this version of Holly, unless Holly is involved with Ian, but then this discussion is moot.
In fairness Holly does touch on it to some degree with Lena at multiple points in the prior chapters, and there is a short discussion with Ian and Emma when they're on the beach with the dog. So she has thought on it, but we as the players and as Lena, hadn't yet had the big reveal of Holly taking slutty selfies and sending them to Ivy; so there wasn't much to discuss from Ian's PoV.