The bathrooms are not strictly for handicapped use as is depicted on the signage. There are also handicapped stalls in the public bathrooms as well that can accomodate those in wheelchairs along with an aide. (I work with the elderly and am very aware of the needs of those who are not ambulatory.)
Companion bathrooms are in place for any person who requires a companion while using the facilities (and that does not exempt children who for one reason or another cannot use a public toilet.) Companion bathrooms are also a Godsend for parents of children with sensory issues.) They are also beneficial to a mother travelling alone with a baby or small child who she needs to keep safely with her while she is using the facilities.
I didn't say the Companion Restroom are only for use by people with disabilities who use wheelchairs. They are -
set up for that use, but some of the features they have make them useful to people with other kinds of disabilities or other people who don't have disabilities.
I wanted to point out that they have raised seat toilets - which is a surprise to many people. Because people call them Family Restrooms, some people expect the ones at WDW to have small toddler sized toilet, which they don't have.
Some, but not all, of the WDW restrooms have handicapped stalls that are large enough to accommodate a person in a wheelchair, plus an aide. Some people with disabilities can't use those stalls because of size, no sink in the stall or the noise level in the bathroom.
I need to use the Companion Restrooms with my daughter, who is disabled.
It does take us a while in there because she is significantly disabled and needs a lot of assistance. It is important to realize that some people may need extra time in there - we have personally had someone call Security on us because we were in the Companion Restroom for more than 5 minutes. The first time they pounded on the door, I did say in a loud voice that I was in there with someone who was disabled and gave an estimate of how much longer we would be in there. I know they heard that because I heard them talking about it. But, they still got Security and demanded that Security kick us out.
We've also had the experience of being yelled at for using the Companion Restrooms because "these are Family Restrooms. You've got stalls in all the bathrooms you can use."
So, my point was people need to be considerate of whoever is using the Companion Restrooms, disabled or non-disabled.