Well, you're talking series, I am talking studios/teams, there's a difference. And, if you are going to talk series, then I'll point out that Nintendo flat out told Ubisoft that they were making a mistake by releasing Mario+Rabbids 2 in the same generation as the original game, and that it would be better to wait. So its not like they have eight hundred people working away at Mario Kart but just not getting there yet, instead those people are doing other games (or, in Mario Kart's case, years of DLC,) and thats fine, assuming that they are actually doing other games, and not sitting around doing whatever it is that Retro was doing between Tropical Freeze and Prime 4 being rebooted.