That nikka Lelouch came back and is basically immortal now.
People just mad they never got the same old contrived Mikasa & Eren happy ending. This was always a war story, if anything the other countries coming in too late was Isayama’s biggest fumble.
I thought it was done perfectly. Adding those other countries, you risk taking the focus off of the main idea which is Marley needed Paradis gone. The only good thing about maybe putting in a stronger focus on the other countries is it showed that as much as the other countries thought the Marleyeans were dikkheads, the rest of the world was still terrified of the Eldians on Paradis.
My thing has always been, if Marley was victorious, what do this "good Eldians" think would have happened to them if the Titans had succeeded in destroying Paradis?
