A little while ago, I chucked together a comparison game on image file formats (incl a stab at av2 images), encoders, parameters to back out preferences relative to ssimulacra2 and butteraugli: https://aadhar.sh/pixel-peeper

It does seem like AVIFs win on small images, and JXL gives you progressive rendering, easy upgradability on JPEGs, and better lossless and high bitrate images.