Piggybacking on this answer, it's also because there is a cost (money, time, knowledge, dev sophistication, etc) to doing it that way.
When people don't see something as an issue b/c they aren't disabled themselves, and it would take extra time / consideration / money to support disabled folks, people won't do it.
That is why in the US we had to legislate handicap accessibility in the real world. People don't build ramps unless they have to.
The other side of it is that the entire enterprise would theoretically not exist without that initial effort.
While it may not appear fair under certain ethical frameworks for someone to receive free money, it seems to be that the choice is "everyone gets nothing" versus "someone gets more than others because they created it".
in my experience, this is a red herring. I know very few founders who don't work harder after an acquisition or capital investment than before. Those who are sitting on the beach tend to have sold their interest.
When people don't see something as an issue b/c they aren't disabled themselves, and it would take extra time / consideration / money to support disabled folks, people won't do it.
That is why in the US we had to legislate handicap accessibility in the real world. People don't build ramps unless they have to.