I finally got enough round-tuits to buy a MicroSD reader, and transfer my Nintendo Switch memory to a 64 gig card. Interestingly, when I did this, it asked to download an update. 

I suspect this is the same as the Sony PS3′s “are you going to use aacs” question in the settings screen. By default, they’re not licensing the systems for that codec or file system. exFat’s only needed for large cards, and not everyone will get a card for their system, so why pay that license for every switch out there? 

But, I guess Microsoft probably got a few pennies richer when I went to a larger SD card…