So you have read the next chapters already? Because so far there's nothing at all that supports your reading. Mei was ready to confess this chapters before Matsuri (like the readers) jumped the gun and started to scream bloody murder over speculations from characters that aren't the ones up to date with whatever happens on the Aihara family household.
Confess to what? Oh wait, we don't know because it was conveniently interrupted. If Mei is engaged again then she has already failed to be trustworthy, she should have told Yuzu a long time ago. It wouldn't have been a big deal since they have already literally dealt with this same situation already.
Yuzu knew form the get go that Mei was engaged to the teacher so your comparison falls apart from the start.
Except she didn't. She didn't even know Mei was her sister. She didn't know that Mei didn't actually love him until she confronted her about it. Again, it's literally another family set up arranged marriage, it's the same exact situation.
And that is precisely why I'm waiting to see where is Saburota going with all of this. Is not the firs time that people here creates huge narratives without basis. Just last month we had people 100% that Mei was dying
No, you did not. People were just speculating, there wasn't a huge reaction like this. We have characters talking about a situation that the whole series started with that all the sudden has become an issue once again. Your comparison might hold water if the series didn't start out with the old and tired arranged marriage trope.
Yuzu and Mei weren't into a relationship, let alone know each other when Amemiya was a factor on the plot and Yuzu step in not because she was in love but because she thought it was the right thing to do.
Himeko and Matsuri are the only ones who have actively try to force their feelings over the crushes. And Sara's confession wasn't a real love triangle since she was fast to step up as soon she was made aware of the situation and her role actually pushed Yuzu and Mei into a relationship.
Narrative wise it's still a love triangle, we were hinted at back then that Yuzu had feelings for Mei and those feelings made her go above and beyond to protect her.
You have a weird definition of a love triangle. Sara's confession is what caused Yuzu so much stress and grief that it finally got her to make her own move in fear that she would lose her chance to be with Mei. Yuzu certainly thought Sara's confession was an actual threat.