While Nintendo is not the company that develops Pokemon, and they also don’t own it, (they control some shares in the company), Pokemon has been mostly released exclusively on Nintendo devices thus far. So we associate Nintendo and Pokemon with each other.
However maybe one day we might see a game released on non-Nintendo consoles. Makes sense right? Sadly for non-Nintendo fans, it seems like that will be unlikely, or at least it seems to be the general consensus according to an interview with Game Informer where an employee at Game Freak was asked about the partnership between Nintendo and Pokemon.
Junichi Masuda, an employee at Game Freak since 1989, thinks that being exclusive to Nintendo has helped the franchise. “Everyone really knows Nintendo; there is a familiarity with the brand, and they have that really strong brand and Pokemon being associated with that and being affiliated with that brand is very important.”
He goes on to say that he doubts that straying to other consoles will happen. “With Pokemon, at least, we really feel it is really important to be with Nintendo, specifically with the Pokemon titles, so I don’t think that would ever happen.” I guess you never know though. The success of the 3DS handheld consoles and the Switch means that there is more reason for Pokemon to remain a Nintendo exclusive at the moment.