>>117232094>that's how most time paradoxes work though
Doesn't matter, if Aku took over the galaxy in the "time pocket" then those thousands of billions of people will always be enslaved to Aku and Aku will always exist there.
It's like if your goldfish dies and your parents get a new goldfish that looks like it. That doesn't make your goldfish un-die. Your parents can say that they traveled in time and got you "the same" goldfish but it's bullshit, it's a different goldfish.
Jack didn't save his goldfish - he went to another dimension, got himself a waifu, used her powers to go to yet another dimension, and then saved that other-dimension goldfish.