I'm not sure if Mario Golf will budge the Switch numbers. I was hoping at this past June Direct that they would feature a game that highlighted a fresh experience for 2021 that would pump sales up for the next two years, but there's nothing... yet Switch continues to kill it on its outstanding catalogue, still up year over year. The lack of a price drop speaks volumes to Nintendo's confidence this year.
I suppose the obvious feature would be fitness - Ring Fit Adventure was a more than successful trial - but those become more obvious titles in the late autumn/early winter when people are seeking some kind of new indoor fitness thing. It just seems like such an obvious avenue for Nintendo - they could release a new type of fitness game every year or two and people will always demand it because, like the majority of recreational activities, they're always going to want something new when they get bored of the old ones... except if it's Mario Kart 8 Deluxe :D
I describe myself as a little dose of toxic masculinity.