I think that one of the issues is that there are many different types of
DAS users, and no one (besides Disney if they cared to look) has any way of knowing how big the populations are. Furthermore, one's perception of DAS probably varies significantly based on his/her own lived experience.
Simplistically, let's pretend that there are 3 types of users:
A: Severely disabled - this group struggles may only be able to manage a couple of rides even with accommodations. I would be willing to go out on a limb and say that no one would really complain about life being made slightly easier for this group.
B: "Average" DAS users - this group faces challenges, but with help may be able to have something resembling a "normal" Disney experience. Number of rides and quality of the experience depends on the day/individual. Eg. I have a friend who is a DAS user who can rope drop AND close the park, but others on the board find advanced selections too challenging and only manage a few rides before having to leave.
C: DAS cheaters (or more charitably those who don't REALLY need accommodations) - perhaps lured by the idea of the 2 advance selections or just the idea of maximizing park time, this group lies/stretches the truth in order to get accommodations. Without having any real limitations, they sign up for the best rides they can in advance, and then will book in park reservations for headliners while they stand in line for other rides, watch a show, eat, or shop. This group clearly has a better than "normal" park experience.
Because so many disabilities/limitations are not visible, it's impossible to know who is a B and who is a C. Disney does their best, but cast members are not perfect and it would be foolish to pretend that the C bucket does not exist. I have said this before but the advanced selection piece is the part that really bothers me because it is not available through
Genie+ and gives a very strong incentive for "C" families to try to game the system, thus degrading the experience for DAS and non-DAS users alike.