Unfortunately too many developers share your perspective. I'd be surprised if anyone building commercial software would move ahead without accessibility support though because, 1. it's required by law in many situations, and 2. it makes good business sense.
It doesn't actually make good business sense to prioritize accessibility. The simple fact that it is required by law is proof: if it was more profitable to bake in accessibility features, then you wouldn't need to require it, companies would do it on their own without being pushed.
