Oh, I would agree with you then. I think most people think just of Nintendo when seeing this games, rather than Koei Tecmo.
But isn't it more important that there are certain companies now that are so close to Nintendo, when previously they weren't? I think Koei Tecmo and Marvelous started it fairly recently.
Their relationships have grown but they go back at least a decade. Nintendo of Europe has picked up Harvest Moon/Story of Seasons games to publish in the past and the studios that eventually became Marvelous First Studio(like Feelplus & Artoon) were developing Nintendo games in the DS and Wii days.