In simple terms, a personality disorder, is characterised by communication problems (usually an unwillingness to share or engage in free and equal or mutual communication), and a tendency to express thoughts and emotions irrationally, erratically, or compulsively. It is also characterised by emotions such as extreme anger and irritability, and an inability to sustain long-term friendships or relationships.
Whilst these characteristics describe a disorder, or a so-called mental illness, there is also a general, so-called normal version of personality disorders, and which keeps everyone in their place, in terms of expected and demanded mediocrity, very base or basic humour, and human and personal imperfections. An ordinary personality disorder, is also characterised by a certain immaturity of behaviour and expression, and by a degree of silliness and flippancy. I also sometimes like to act silly and be flippant, but I also like to take myself and others seriously, and which the ordinary personality disorder often militates against.
There is therefore a tendency, for ordinary people, to attack or criticise those who try to break out of this pathological conformity, and label them as pathologically insane, paranoid, psychotic, or deluded, particularly if the person, does not want to be a part of the crassness, stupidity, mediocrity, and ignorance of the ordinary personality disorder. If a person tries to break out from this conditioning, then ordinary people say that they are mad, take themselves too seriously, or that they have no sense of humour.
The mental health professionals, and social workers, also absorb and embrace the pathological conformity, and social control, of the ordinary personality disorder, because they think that this helps them relate to other so-called normal people, such as people diagnosed with mental health problems, and because the professionals see themselves as ordinary people, although they can't see in fact that they are acting and behaving like arseholes.
Whilst I agree that humour is very important, and that we should all be able to laugh at ourselves, the British have a very sadistic sense of humour (and which is sometimes pointed out by other cultures and races), and are often only happy when laughing at someone else's expensive, and when those laughing can't take it back, or laugh at themselves in turn. If everyone could laugh at themselves, this would be a good thing, but often laughing at yourself, is something that others expect or demand, who can't do this themselves, and so it is a matter of double-standards, and very one-sided.
People on the right-wing of politics, sometimes complain about political correctness, that it censors language and free speech. Political correctness is up to a point a good thing, because it is about expanding language and terminology, instead of just using the same old derogatory and abusive language and terms.
Political correctness in humour, started off in the sixties with the anti-establishment humour, and then in the eighties with alternative humour, and which was all about poking fun at powerful, and rich people, in authority, instead of making fun of minorities, poor people, and people with diagnosed disabilities.