“These limitations are all reasonable for the web use case, but not for a general-purpose image format.”
JPEG XL can losslessly shrink existing JPEGs by about 20 percent and rebuild the original bit for bit. It beats AVIF by 10 to 15 percent while encoding three times faster. Google killed it in Chrome anyway, and Google happens to back AVIF. The format with the better numbers lost to the company that owns the browser.