@Enzeru:
How is running away into a fictional world where everyone's pseudo-happy going to solve anything? Even that aside, how will they all survive that state of hypnosis without dying in a few days' time? Is Madara opting for a superficial paradise that lasts one or two weeks tops and that leaves him as the sole survivor once everyone else is dead? Just making this thing work is already stupid enough, let alone trying to justify its usage.
Of course it's difficult to achieve world peace. It takes the combined efforts of everyone and a long period of time to get somewhere. It's something you have to work for, not just use your magic eyes to lull everybody in a false sense of happiness. And let's not even get started on how the people would react to that and what they'd think of living in a false reality.
But this manga doesn't even deserve that kind of discussion for it's done barely anything to warrant it (world-building, characterization etc).
I'm not saying his reasoning is right, I'm saying that its not a bad goal for a villain to have. I think the Genjustu will work as a sort of subtle mind control, basically repress any confrontational emotions where everyone is just happy eating and dancing and shit(I don't think people will just stand there like zombies) and as you've pointed out there are some logic holes in that reasoning but we've seen a lot of "grey" villains have this, heck pain's shtick was sort of the same only he intended to create peace through fear something that would have worked at least partially.
Thing is Madara has already done what no one else has done he's united all of them due to his threat and ambtions(I'm sure this is what he'll say at the end) the only thing is what stops them from going back and starting plotting to take over, what stops Kumo from its militaristic ambitions or Konoha for playing the guider of the world even it means invading other villages, or taking jobs of assasinating or whatever shinobi do that leads to conflict to make money or whatever.
I think that's part of his reasoning. Force them into a prison where everyone is happy instead of living free and always at war although it doesn't change the fact that its still a prison.
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@MetaMario:
I thought it was kinda neat? that Byakuya actually gave a compliment for once, and Rukia technically won…..but what was the point of him come in if she had Bankai? The victory feels so damn hollow. I mean, compared to Aaroniero....she didn't have someone to help....
I took at as Byakuya going there for revenge, I mean he has every right. Finds his sister-in-law doing her best to kind of avenge him and decides he'd rather take that than the revenge.
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@MetaMario:
I thought it was kinda neat? that Byakuya actually gave a compliment for once, and Rukia technically won…..but what was the point of him come in if she had Bankai? The victory feels so damn hollow. I mean, compared to Aaroniero....she didn't have someone to help....
I took at as Byakuya going there for revenge, I mean he has every right. Finds his sister-in-law doing her best to kind of avenge him and decides he'd rather take that than the revenge.