>>58839339OP here, i just went on the literal basis of "newer", ie. more new than old. the first four gens are closer to the beginning of the series - more old than new - and the latter four are closer to the present day - more new than old. unova sits in the middle, so its neither more old nor new.
i went with the simplest, most literal definition i could to try and avoid genwarring. please just stick to posting cool mons