Guest convenience for resort guest should not be Disney's goal? Having medical equipment delivered isn't generally treated as a luxury like a car rental or groceries. It's not optional for people who need them. The world is hard enough as is for people who aren't abled bodied.
Also, Disney has not ever guaranteed complimentary wheelchairs will be available at resorts which is why on their own website they recommended 3rd party companies. They generally have less than two on hand, if that.
Disney is one of the better companies for disabled people but even they fail at times. For example in August, I went to get a water wheelchair from typhoon lagoon (which Disney states are complimentary for guest) and when we arrived, they told me both had broken months ago and would not be replaced.
At haunted Mansion, out of the 10 attraction provided wheelchairs available, 6 were broken.
The new tower at Coronado Springs doesn't have a single handicap accessible door leading out back to the rest of the resort.
Again, I'm not going to argue. We can respectfully disagree on how it should be handled. I 100% feel like exceptions should be made for mobility/medically necessary devices