No, the situation about image compression has not changed. The Grand Poster you were replying to was writing about typical web usage, that is "medium-to-heavily compressed images", while your benchmark is about lossless compression.

BTW, I don't see how Mozilla's interest in a jpegxl _decoder_ (your first link) has anything to do with the performance of jpegxl encoders compared to avif's encoders. In case you're really interested in the former, Firefox now has more than intentions, but it's still not at production level: https://bugzilla.mozilla.org/show_bug.cgi?id=1986393