What you're ignoring is that WebP is from the year 2010. JPEG XL is from 2022. Incidentally, JPEG XL is also a Google project, making your ranting about how bad they're at image formats pretty funny.
Hi!
I'm aware that JXL partially originates from Google's PIK - and also Brunsli??, but I had indeed forgotten that WebP started in 2010, wow, 13 years old already.
I'll therefore correct my statement: "How could Google do worse than that??? When basically rezipping (with a modern algo) the existing DCT macroblock bytestream of a 18 year old codec beats your new codec, you should just trash it."
Also, Stuffit's SIF format is still 5 years prior to 2010 so that point stands.
I didn't compare with stuffit. If it's better than JXL recompression, perhaps they had put more focus on lossless recompression. Perhaps they had less realtime constraints in decoding speed.
