Because really effective anti-ablist work is about as old as I am. Barely. (There is a much longer history and they were very important! But they were also incredibly hampered, limited by circumstance and difficulty to very specific areas, and had limited successes.)

Because as recently as twenty years ago disabled people just disappeared and the vast majority of people knew, if they knew anyone, one otherwise totally cognitively normal person who used a wheelchair due to an injury or amputation.

And because being other than ablist requires not only being aware of the issue and wanting to deal with it but also fully and completely grappling with issues of conditional privilege, competing and mutually exclusive access needs, and all the other wrinkles that most people would really rather . . . not. Or would rather consign to "okay but I have THREE axes of oppression and you only have two, so I win."

/cynicism