Just one clarification about this: As stated before in these comments, JPEG XL includes brunsli, so JPEG XL allows for byte exact transport of the original JPEG

Just one clarification about this: As stated before in these comments, JPEG XL includes brunsli, so JPEG XL allows for byte exact transport of the original JPEG file (with -22 % in size). This can be practical for example for file system replication or for long term storage of a lot of original JPEGs. The other, non-brunsli JPEG XL modes can do pixel exact, but byte exact can be more appealing for some use cases.