For first party stuff, Nintendo launches finished games

This wasn’t true for several Nintendo games. Mario Kart 8, Animal Crossing and Zelda:Tears all required day one downloads.

Unfortunately there is a fair number of games with a physical release that require downloads to be playable as they are not complete on the cartridge.

Not always true: Not all physical copies contain full copies of the game and will require downloads before the game can be played.

Animal Crossing being a prime example. Mario Kart 8 requires 4.4 GIGABYTES to be downloaded before the game is playable. There have also been cart revisions where earlier versions of the game were complete on the cart… and newer versions of a cart were partial and required downloads as a cost saving measure.