People make judgements about others all the time.
It is not just about disability issues - it can be related to gender, the colour of one's skin, where a person was born/lived most of their life, religion, and sexual preferences, among many others.
However, in terms of disability, the "professionals" (doctors, consultants, therapists, social workers) perceive people in one of two ways; the 'medical' perception or the 'social' perception.
The 'medical' perception focuses on the purely medical aspects of a disabled person's life. It ignores everything else, and insists on responding to the person in terms of perceived medical need.
As a contrast, the 'social' perception can ignore the physical limitations arising from disability to the extent that one sometimes has to actually point out that there is a reason why an individual cannot achieve some target, and that disability is the reason.
It is a shame, in my opinion, that the two methodologies cannot combine more often than is the case in Real Life to create a third, and much better, 'holistic' perception.
It might cut out some of the misconceptions for everyone and reduce the occurrence of judgements being made on any grounds.
For example, even in the twenty-first century there is still the feeling among a proportion of the population that a person with any physical or intellectual impairment must be "supervised" when out in public!
Why?
True, some people need the guidance of another person to ensure that they do not do something hazardous like walk out in front of traffic.
However I, and very many other people, am quite able to go out in public without an attendant. If I need help while out, I'll ask, and by-and-large people are very helpful.
To apply this reasoning to everyone with a disability is like saying that everyone who uses glasses for reading only must be very poorly sighted! Incidentally, I fall into the category of needing glasses for reading, but that is all. No offence is intended to those visitors to this site who have low visual ability - or who only wear glasses for reading.
The example is intended to show how ridiculous it is to assume that just because some people need help, that everyone does!