User blog comment:AndrewBrauer/Discussion - Is Luna Loud becoming Irrelevant in the series?/@comment-30592229-20170327213437

Another thought I had is that it could just be due to the way season 1 played out.

Sisters that had more than one episode starring them in season 1 (Lori, Leni, Luna, Luan, Lynn.) Haven't really been given a whole lot of focus in season 2 (or at least the beginning)

But the younger sisters got no love last season, the closet thing to a Lisa episode was butterfly effect. So I think they're focusing on the younger sisters if they chose to focus on any right now.