>>35577266New gen = New Pokémon native to new region. Official marketing has confirmed this, Masuda has even confirmed it on his blog.
Given that the leaks said it's a Yellow remake and mentioned nothing about new Pokémon or a new region, we know it's not a new gen.
It doesn't even work in reverse; games in every gen can trade directly with one another. That would mean you'd be able to datamine these games and find the next batch of 70+ Pokémon before they're even announced. If you disagree with that, you're concluding that the next batch of Pokémon will be Gen 9, which means that Gen 8 will be the only Gen with 0 Pokémon.
