Why?
I don't think reviving the characters is 100% bad but the worst part is the newer characters since they don't fit into the theme of the story and are very generic or downright cringe(looking at you Mizuha )
also the introduction of those characters made the revived characters get sidelined
also all the conflicts are cringe especially that pedo brother
even the main character of this arc is cringe aka Mizuha who killed her non abusive mother for shit and giggles (yes people can be upset when they are stressed but under no circumstance should they kill their relatives or friends)
I actually agreed with that especially mizuha's character. And yeah the pedo oniichan is cringe af but the author is trying their best to not make it too complicate since it's only the beginning of the new arc. Maybe there will be a huge storm after this ¯_(･ω･)_/¯
This is basically the worst arc in this manga