Yea no tbh i think Ring fit will get DLC or new free updates since the game is blowing up. No need to do multiple ones cause i really don't think it has potential to be a franchise so quickly. I mean the game is quite expensive and people don't seem to be tired of it already. I do think maybe this can become a thing they use as an argument for next gen.
And for the Switch cycle, we will have too see but we know Nintendo are planning to have a really long life cycle for it, it has been said. The DS got cut short cause they were scared of the new PSP coming out. Now with no competition in the handheld departement they don't really have to fear, and the home console departement is less of a competition for them. So i think we won't see a new console until sales really start fading away. But with only 1 system, i also don't think they will wait till it does like 6 millions a year either. So maybe end of 2023 or March 2024.