> Accessible video/audio is pretty much not existing.
He should have read more completely because the almanac notes:
> … this figure may not account for video content loaded by a third party <iframe>, such as an embedded YouTube video. It should also be noted that most popular third-party audio and video embedding services include the ability to add synchronized text equivalents.
And that note is off mark as well. Most audio/video players load captions/subtitles out-of-band and do their own rendering or add them to the video element via JS for greater control.