People are quick to blame Google for the slow uptake of Jpeg XL, but I don’t think that can be the whole story. Lots of other vendors, including non-commercial free software projects, have also been slow to support it. Gimp for example still only supports it via a plugin.
But if it’s not just a matter of Google being assholes, what’s the actual issue with Jpeg XL uptake? No clue, does anyone know?