Lastly, why is everybody getting so frustrated. Their misunderstanding is similar to
How I attended an all guy mixer where they are fumbling around while trying closing the gap.
This isn't them fumbling around. This is them being actively separated with other characters preventing them from talking to one another.
And it happened twice in a single half-chapter, and the second time by the character who claims to be a friend, but seems to still outright dislike Sorata and has undermined Miyuki as much as she's helped her.
They've been "fumbling" since before the Kyoto trip. Ayano brought things to a head by getting into Sorata's brain and convincing him to confront Miyuki about returning to Kyoto...which
should have been the moment they both fought it out over what they really want from this relationship and what they mean to one another.
Instead, Miyuki went "oh, you want me to leave school and come back? Okay bet" and she just walked off, then mom told them to stop talking and go to bed, and then Merry said "nah the engaged couple doesn't get to spend time together in Kyoto, I'm gonna split you up even though I know there are things you need to sort through".
And that's basically volume 4, into volume 5, with no resolution on any of the problems present and only more added on.
It does become a bit of a slog after awhile, when
no items are crossed off the To-Do List and it's because the supporting cast is actively interfering in the lives of those they claim to care about.