In 2020 I came across this question on-line last year in 2020 and the answer to this question is in my honourest response to this is both Yes and No,
In my personal case I had epilepsy as a adolescent in my youth aged 12/13 back in 1992/1993 and this has led me to believe that I have suspected permanent neurological damage to the muscles controlling my bladder.
However as each person is different it really depends on the situation one finds themselves in no pun intended.
Personally speaking from my perspective I wear them both because of the fact I have to do what ever keeps me clean and dry and this meant making some personal sacrifices since becoming partially incontinent in 2010 aged just 30, through no fault or desire of my own.
But the simple fact is that I also have to wear adult sized disposable diapers/nappies for reasons of practicality and comfort/personal hygiene.
When I am in diapers I can safely regress back to a more simple/innocent time as specially when I get stressed out or suffer from episodes of PTSD and other psychological reasons although that's a topic for another day.
And yes I fully accept that there are some who need them genuinely more than myself and at the other end of the spectrum however there are those who don't need them at all,
this puts me somewhere in the middle of these two spectrums if you can imagine a see saw as a scale of where I find myself.
but on the other side there are those who choose to wear them anyway and there's nothing wrong with that at all.
As saying goes each to their own as long as no-one gets hurt or any laws are broken,
There are also those who have to wear diapers/nappies because of the job or career they are in such as astronauts/explorers, factory workers and scientists or prison guards and or deep-sea saturation divers
and some sports such as some racing car drivers or pilots in Aerial aerobatic compititions or millitary pilot's who have to wear them because of obvious reasons.
Personally as for myself I wear them as my chosen form of under-wear in order to help avoid embarrassing situations as per my earlier replies.
As for weather its mortally wrong or right I will leave that up to you, personally speaking I don't judge anyone and never will do so.
As in my mind stigmas simply don't exist and in my humble opinion if people want or choose to wear diapers/nappies then they should not be bullied or looked down on by society,
as specially given that anyone at any point in their lives will have to wear them as specially in cases of disability or getting old.
It's about time that society as a whole comes to realize that wearing diapers/nappies doesn't make anyone less human and people should come to accept this fact
As specially given that most people like myself have hidden disabilities and to make fun of them is to automatically discriminate against these people.
Discrimination and bullying in any shape or form is not only wholly wrong but illegal, period and should be eradicated at all costs.