Regulation is not free and doesn't magically make our wishes come true. It just moves costs around, hiding them and often preventing the free market from minimizing them.
The difference between rich countries, the government forces the businesses to accommodate people with disabilities at the cost to the business. In poor countries, at least the one I came from, they leave it to the businesses to make that decision themselves. The result is that in rich countries are much more accessible than poor countries.
I don't know if your model (where "the society", which I guess means the government pays for this stuff) is tested in any jurisdiction. If it has, I would appreciate a link to an article about the results. But the model where businesses are forced by regulations to cover the costs works very well, as evidenced by how accessible US is thanks to ADA.
My point still stands—unless the society via regulations forces businesses to accommodate groups like people with disabilities, those groups will be excluded from society, as they are in my old country.