To me that argument doesn't make sense... It seems like arguing that because there are wheelchairs that can climb staircases, there's no need to make buildings wheelchair accessible.
I thing the problem with this argument is that it shifts the burden of serving all people (including disabled people) from the company providing the service to a person who is disabled. That's exactly what the ADA was supposed to prevent.
No, it's like if we had wheelchairs that were so broken and unstable, everybody had to build ramps with very special and hard to maintain padding on it, which varied between wheelchairs.
It's the responsibility of the wheelchair makers to at least build a reasonably stable product that everybody can support.
I thing the problem with this argument is that it shifts the burden of serving all people (including disabled people) from the company providing the service to a person who is disabled. That's exactly what the ADA was supposed to prevent.