Think it's more that kirara Momo is still stuck in training training training addition as though it's the only thing she knows. While current real Momo shows development a one note character can't show, she's already realized shamikos strength.
That's what kirara Momo is missing, kirara Momo is a one note character, while machikado characters are not one note like that. They think and do unexpected things sometimes. Momo instead of jumping at the chance to train, acknowledged shamikos strength.
Characters in this series can't change, but they can grow. No amount of training will ever make shamiko physically strong. However by understanding her own strengths and maximizing them, can can overcome any obstacle she needs to. The chapter is about characters trying to change who they are, but it isn't working, instead they need to realize their own inner strength and maximize that instead. Shamiko powers up through determination, not sports training. Riko powers up by applying her disguises and various skills better. Ogura powers up by utilizing her intelligence better. They're like a machine, not all parts in the machine can serve the same function, but if they all work together with their own strengths, the machine will run well.