I dunno how much they pay attention to the fandom and things such as RNG, but if they do, maybe they'll try to blot it out. Assuming they pay attention to things like that, they know that 3DS RNG hasn't been cracked and that we have little chance to crack it as we are now. Furthermore, they know that gens 3-5 have been heavily exploited. So if they want to blot out RNGing, they will not include a way to migrate Pokemon.
On the other hand, they would also know that the fandom would be pretty upset if they can't send their favorites to the new games.
You can't count this out, folks. Remember Gen 3? No way to send Pokemon from Gen 2 to it. If they decide to change the mechanics again, they actually COULDN'T allow for a transfer. It's a definite possibility.