Re: Wait, i can't trade to the new Generations!?!?
IVs used to only go up to 15, and EVs didn't exist, instead there was "stat experience" which was a sort of early form of EVs. That and no natures, so yeah, like it's been said, old Pokemon wouldn't "compute" on the new games.
Also in the old games, whether a Pokemon was "shiny" was based on IVs, and now it's based on PID, so it wouldn't work there either.
I'm glad that things start to become untradeable, it helps so that they can actually update the mechanics and make them fit. :)