AV1 looks very cool but it doesn't have nearly the level of compatibility that H264 has. H264 works out of the box on browsers, as well as having hardware support on phones and SBCs and set-top-boxes and whatnot.
AV1 might eventually get there, and that would be awesome if it does, but H264 has been around long enough to have a substantial "first mover advantage" over AV1.
AV1 might eventually get there, and that would be awesome if it does, but H264 has been around long enough to have a substantial "first mover advantage" over AV1.