You are arguing from an abstract position. The universities in question have already chosen to provide free educational resources and are now being sued to provide a reasonable accommodation to allow a subset of the population access to those resources under the aegis of the law.
Old joke:
A marxist economist meets a market economist at a conference. After listening to an exposition on Smith and Hayek he nods vigorously and says "Yes, yes! I know it works in fact but does it work in theory?"
Just to clarify the position you're arguing for. A university has a bunch of existing videos that have been taken of lectures. Someone asks "can I put these online for free?". The answer should be no you can't unless you're willing to have them all transcribed.
I suppose it rests on the definition of reasonable accommodation which could range anywhere from "making the material available for transcription" to "full professional subtitles should be made available".
I think the law applies to new videos that are created for distribution online. I don't think it applies to videos created before the ADA was passed that are put online now. Or a private conversation that was published.
A building is not a video. An older private residence does not have to be upgraded to be ADA-compliant. A video which is intended for mass distribution should have some effort put into accessibility.
Old joke:
A marxist economist meets a market economist at a conference. After listening to an exposition on Smith and Hayek he nods vigorously and says "Yes, yes! I know it works in fact but does it work in theory?"