Yeah, games like Mario Odyssey, Mario Kart, Luigi’s Mansion, etc. are fun as hell and very polished. I can’t think of a single first-party Nintendo game that’s released riddled with bugs in recent memory, whereas the rest of the industry can’t say the same, excepting Sony’s first-party games.
I don’t think Pokemon is first-party since that IP and the dev studios fall under The Pokemon Company, whereas games like Mario and Zelda are developed by studios within Nintendo itself. I could be wrong.
Edit: I just looked it up, and yep, Nintendo only owns 33% of The Pokemon Company.