DNG isn't really related to JPEG XL at all AFAIK. DNG is a standard-ish way to shove RAW images in a TIFF file. DNG doesn't have to be tiled, but if you do have

DNG isn't really related to JPEG XL at all AFAIK. DNG is a standard-ish way to shove RAW images in a TIFF file. DNG doesn't have to be tiled, but if you do have tiled RAW images and want to compress them, then it seems like JPEG XL might be the right tool for the job there.