Winbtrfs has some really funky bugs (some apps like Aseprite will somehow make files which get padded up to a round KiB size on disk which breaks some file formats, even though it doesn't do that on NTFS or FAT), is way slower on Windows (longer loading times, streaming asset delay, delayed audio on some situations like RPG dialogue, Skyrim mods are especially problematic, blah blah blah), the extra permissions make managing it annoying, and symlimks generally just don't work on both Linux and Windows at the same time no matter the FS which can occasionally be annoying. I really wouldn't bother with winbtrfs for games unfortunately