While the idea of pokemon typing has already been shot down before, I believe enough time has passed and enough rules have changed to really consider pokemon types. It would simply be convenient to look up pokemon by types, and while there'd be 700 or so tags to change, I think implying a pokemon's types on its species tag would be a simple and appropriate change.
Even considering intensely humanized pokemon, they're still based on the original species, with its types.
I've considered this because I have actually had troubles trying to look up pokemon types before, trying to find good art of poison and grass types specifically. It's tedious to look up "~pokemon1 ~pokemon2 ~pokemon3" and it's just ineffective, and you can't even use further ~tags from there.
The one hiccup here is hybrid pokemon, but I believe since the pokemon forming the hybrid would already have their implied typing, that would be taken care of outside of fringe examples.
tl;dr it's simple, effective, and convenient, why not?