SDXC cards can be reformatted to use alternative file systems. For example, FAT32 supports volumes up to the SDXC's maximum theoretical capacity of 2 TB as well, and technically it can be used in a SDXC host device that can handle volumes larger than 32 GB, if the device can support the card's file system.
However, in order to be fully compliant with the SDXC card specification many SDXC-capable host devices are firmware-programmed to expect exFAT on cards larger than 32 GB, and consequently may not accept SDXC cards reformatted as FAT32, even if the device supports FAT32 on smaller cards (for SDHC compatibility). Therefore, even if a file system is supported in general, it isn't always possible to use alternative file systems on SDXC cards at all depending on how strictly the SDXC card specification has been implemented in the device, and it bears a risk of accidental loss of data, as a host device may treat a card with an unrecognized file system as blank or damaged and reformat the card.