Well it's a good explanation, and I've just looked at the ADA requirements citing what you're specifying, but perhaps it's a case of older construction and time.

The 1991 requirements don't seem to mention this, and it wasn't until 2012? that the new rules came into effect it seems. And that's only for new construction or alterations. How many elevators are legacy? And it's not like I use elevators daily, I think the last time I used one was 2 years ago.

But an interesting dive into it. Thanks for responding cogently.