Louie on 13 June 2017
I think they will release Mario Kart 9 later in the Switch's lifecycle. There's no reason for a new game in 2018 but late 2019-20 could be good. Mario Kart is a big system seller and could help carry the platform in the later stages of its life.
Of course, they could also make another Diddy Kong Racing game, make that really great and have two fun-racers with great sales on the same platform. I'm sure Nintendo could convince most of the Mario Kart audience to give Diddy Kong Racing 2 a chance (hell, just put some Mario characters into it) so that could be a great idea.
