I can't remember exactly how many, but it took quite a few years for Game Freak to eventually finish the original Pokemon games and after that they had to deal with the amazing success and create the sequels Gold and Silver. By that time there probably wasn't enough time to make another Pokemon for a big console like the SNES.
The reason why much older consoles only have bootleg/demake ROMs of Pokemon is because during that era, Pokemon didn't really exist.
I meant in japan, they got Pokemon in late 1995/early 1996, so i thought Gamefreak could of made a Super Famicom game