How about you educate yourself, say, 4 seconds with google?
FAT32 supports up to 2 TiB with 512 byte clusters.
exFAT supports 128PiB with a theoretical maximum size of 16EiB.
I am referring to the SDHC and SDXC specifications, not the filesystem specifications.
Nintendo so far as adhered to the SDHC standard, and with the switch will embrace the SDXC standard.