"Wow, that's a thought! Can you really do that? I don't see why that wouldn't work, unless Ganon is secretly an intelligent manifestation of the world's people's hate and evil, in which he might follow us there, which is possible! We don't know what he is, really. And there's a lot of beings which could be hard, dangerous or even lethal to evacuate, like the Great Fairies, or the deep-sea Zora, or the Minish, or the dragons... and legendary realms like the Twilight Realm or Dark Realms or the Sacred Realm... a lot of things we don't know to be confirmed to exist, but some of them probably do!
"If we end up leaving them behind, they could end up eaten by Ganon; or the people that do go might suffer for separation or other reasons we can't predict. What if the legendary Dream Stones are real and we forget to take along and on the new planet no one is able to sleep because of that? The Subrosians from the deep mines of the Continent South of the Sea, which I do know exist, they get thinner and weaker the longer they are away from their homeland, and it's not solved by digging new mines to live in Hyrule or lava baths or importing a lot of their special lanterns. There are a lot of mysteries like that!
"Also, you're not going to convince most of the world to follow you to a different planet until Lynels are overrunning their walls, no way."