Before I used EXFAT on my main 256GB microSD card, I had a spare 64GB card formatted as EXFAT and installed larger NSPs to it, then copied the newly-created folder in '/Nintendo/Contents/registered' to my main SD Card. Even though the EXFAT microSD card can handle large file sizes, the Switch still splits the 4GB+ NCA files into 4GB chunks ('00', '01', '02', etc) inside the NCA folder.still 4+GB .nca wouldn't be able install to fat32