At a previous job, that was the justification for a mandate to make sure our website and mobile app was accessible prior to its general availability. (It's also the right thing, as we knew, but the existence of a legal requirement tends to give doing the right thing a lot more priority in a team's backlog. So there's at least one case of the law working as designed.)
See also https://en.wikipedia.org/wiki/Americans_with_Disabilities_Ac... -- the experience I'm talking about was prior to the mentioned 9th Circuit ruling or the Supreme Court's 2019 declining of the appeal, but the laws were on the books already. I don't remember exactly whether the Target case is what was mentioned as a motivating factor to us, but it might have been: <https://en.wikipedia.org/wiki/National_Federation_of_the_Bli...>
(I say 'possibly underenforced' because I don't really know enough about the accessibility landscape, but I somehow doubt that every customer unlawfully prevented from accessing services that the ADA covers actually sues...)