I (obviously) can't say anything regarding Steam Deck; so general reply:
Official SD Formatter applies the standard file system according to the standard.
SD: FAT16
SDHC: FAT32
SDXC: exFAT
Journaling filesystems have traditionally been a problem on SDs (or older flash devices like USB thumb drives) leading to low performance and even decreased lifetime. No idea if this is still a problem nowadays.