Alas, I don't think this is easily feasible. See this case with UC Berkeley:
Any university that would do this could get sued, and universities have already been sued, as long as they don't invest thousands of further dollars into captioning everything correctly.
Edit: This still seems like a good idea, so "don't think this is easily feasible" was too strong of a language. I appear to still be salty about what happened to the Berkeley archives.
I'm no expert, but I doubt that that's as much of an issue as it sounds. My understanding is that the Berkeley thing was based on a DoJ finding, not an actual lawsuit. If it were a lawsuit, then it would serve as precedent (at least until overturned by a higher court, which is usually how such stupidity would be fixed). But as a DoJ finding, I believe it's much less binding - a future DoJ (i.e. the DoJ we have now) can just stop issuing such dumb orders. Given the current position of the political see-saw, that's exactly what I'd expect - this is not the particular brand of stupidity one expects under a nominally-Republican administration.
Even setting aside my guesses on that front, legal problems about making videos publicly available are definitely the sort of thing one can worry about later. The ADA definitely doesn't ban just pressing the record button.
Do you think that triggers if they don't post them on a website, and instead just accumulate the recordings? Which is what I assumed john to be suggesting.
[leaving aside for now statements like "geez the world is bad"]
I think it's in a legal grey area, but not confident. It might be totally fine if it's just individual professors doing their thing, without any backing from the university, though I think I have some trouble seeing how that would be different from a legal perspective.
My recollection was the problem was about the professors making things available to some students without making them "available" to all students.
Over the years, I've made very heavy use of open courseware/MOOCs. I'd estimate that I've covered about as much material in online lectures as I did in-person during a four year degree.
However, since college I've been frustrated by the general lack of online material for non-101 courses. Sites like coursera, edx, etc seem to have realized that the vast majority of users have basically no relevant background, so they optimize for users with no relevant background - they produce a very repetitive stream of 101-level courses. More advanced material is harder to come by online, even though it's abundant in university course catalogs.
But I hear that many colleges are moving courses online in response to coronavirus. So, a request for any professors out there: press "record" during lectures. You're on video already, you can sort out the details and decide whether to actually put up the recordings later, but for now just push the record button.