I really don't like this arc, but I'm willing to wait it out because it does feel like the culmination of something that's been building through volume 3. I felt like the end of volume 2 was a bit of a turning point for Yamada, and while she's not magically fixed of all her issues and insecurities, volume 3 really highlighted how she's become a lot more mature, focusing on not just her future career, but also her future life with Kase. On the flip side, this growth from Yamada highlighted how Kase hasn't really grown much throughout the course of the series, and now that Yamada has come so far, it's high time for Kase to catch up.
This whole ordeal came about because, for all her popularity and seeming confidence, Kase is actually remarkably insecure herself, and she desperately wants everyone to like her, and to avoid any kind of conflict. Fukami pressed this issue, and Kase folded. And this chapter made it clear that she just assumes Yamada is going to go along with it, and why not? She always has in the past after all. So what I'm really hoping for from the next chapter is for Yamada to (finally) assert herself to Kase, and force her to realize that she can't always make everyone happy.
If the author actually delivers with real character growth for Yamada and Kase, I think it would salvage the arc for me. But if they cop out, and it ends without Yamada asserting herself, and with Kase just winning the race and everything getting swept under the rug, I'll be really disappointed.