One case where JXL is very noticeably more accurate is here: https://storage.googleapis.com/demos.webmproject.org/webp/cmp/2021_06_08/index.html#meg-20110701-ja

One case where JXL is very noticeably more accurate is here: https://storage.googleapis.com/demos.webmproject.org/webp/cmp/2021_06_08/index.html#meg-20110701-japan-expo-02*3:1&WEBP2=m&JXL=m&subset1 https://storage.googleapis.com/demos.webmproject.org/webp/cm... The singer’s left hand has wrinkles in the original image that disappear in WebP2. Overall, WebP2 and especially AVIF are really good at very low bitrates (<1 bit per pixel), but unlike video, images on the Web will always be shown at the smallest bitrate necessary to be indistinguishable from the original; there, JXL tends to show all the details at a lower bitrate.