[Rule35]

> For a lot of these websites it would necessitate a lot of manual work

Yes, but ... That's work they brought on themselves by not doing the right things in the easy way. Sure, once they're there, there is a lot of work to come back but that should be used as a reason to not use those frameworks in the first place.

Some accessibility is like adding alt-text. It adds work. But almost everything else is just not abusing the browser and is generally done simply by following the recommendations. And not trying to live on the bleeding edge.