The TLDR summary is that AVIF was going to be the next generation standard for image formats but when JPEG-XL released with a near identical feature-set, better quality compression, and backwards compatibility with JPEG, the tech world put its support behind JPEG-XL.

Naturally, Google as one of AVIF’s creators was unhappy that the standard they control looks like it will lose the format war and so they decided to use their web monopoly to kill JPEG-XL in the cradle by killing support for it in Chrome around a few months ago.

While this has slowed JPEG-XL’s momentum by a lot, even the other co-creators of AVIF like Apple, Meta, and Microsoft are still putting their support behind JPEG-XL and it seems like they would rather force JPEG-XL adoption themselves than go back to AVIF.