The approach used by Australian universities is exemplified by the University of Western Australia, which says: "Captions, a transcript or lecture notes for the uploaded video must be published at the same time as the video. Google's auto-caption feature can be used, but the captions must be edited."
However, my impression is that Australian universities mostly provide captions for video materials which are used repeatedly, such as in MOOCs and other packaged on-line courses. One-off lectures are not captioned, nor is a transcript provided, just lecture notes. Presumably universities are relying on the 'unjustifiable hardship' provision in the DDA, to say it would be too expensive and difficult to caption all lecture videos.
But as Marianne Stenger noted, the closed captions can be useful for students generally. In particular these are useful for those with English as a second language. University education is not a cottage industry, it is Australia's fourth largest export and perhaps it is time to provide closed captions for all video lectures.
However, it should be noted that on-line courses do not necessarily require video. Most of the on-line courses I teach and am a student of, do not have video. These courses have text based notes and discussion forums.
ps: I am not a lawyer or an accessibility specialist, but was an expert witness in the Human Rights and Equal Opportunity Commission web accessibility case, Maguire v Sydney Organising Committee for the Olympic Games 2000.