But why is this tolerated, for lack of a better word? There's no barrier to adding support, a decoder ships with ffmpeg. Youtube has been serving webm/vp9 video for years, so does that mean VP9 Youtube is unavailable on Apple platforms?
Youtube serves h.264 to Apple platforms.
And yet, things continue to work and continue to progress for the most part, so format wars aren’t necessarily as big a problem as we like to think.