It would be easy money, but knowing Nintendo, it won't happen.
Juuz. Just because a few people on a forum happen to like the idea, and that group includes you, does not indicate it's financially viable, let alone "easy money"
This board is just a small sample of users, but it appears that the idea is popular elsewhere as well. Hell, at the local used stores, copies of any pokemon game go quick, and I hear a lot of people asking if Nintendo would ever release the games digitally.
It would be a good seller in the eShop. Most things pokemon are.
The only problem I see with porting the code over is the trading mechanic in the game. It would need to be worked on to use either local multiplayer or wi-fi, with local multiplayer probably the easier of the two (closer to the original in execution, since the 3DS has no need for a link cable). Nintendo would likely want to keep the ability to trade, and that may be what's stalling it.
Though, if I remember correctly, and I likely don't......while emulating the GBA versions on a PSP it was possible to trade pokemon with another PSP emulating a GBA pokemon game. I don't remember since I never really bothered.