Well that's just factually incorrect. Last 10 years we've had xenoblade series, splatoon series, labo, arms, codename steam, wonderful 101, pushmo series, steel diver, art academy, Dillon rolling western, ever oasis, snipperclips, octopath traveller, sushi striker.
Next year has daemon x machina, town.
I agree with your point however ... Octopath Traveler doesn't count as it's not owned nor created by Nintendo, neither does Daemon x Machina. Some of these they're publishing but that's not really the same thing, unless you want to claim Nintendo owns Dragon Quest
Also I don't think there's really anything risky about a lot of these projects, most of them you listed are very low budget titles that would make an easy return. I think something like Sony's Last Guardian or even Days Gone (mostly because the developer has no real pedigree) is a lot more risky.