Sorry, but that’s just navel gazing drivel. It is entirely different to neurodiversity. It is a made up phenomenon fuelled by the desire to be seen as ‘queer’.
Personal validation of what precisely? What would you define ‘asexual’ as?
Asexuality is not a made up phenomenon. It is a normal part of being human. It is a normal part of maturing from childhood to adulthood. For most people it is a temporary condition, disappearing at some point during or after puberty, but for a minority of adults it persists and they never feel sexual attraction to another person.
If you are 16 and your peers are all discovering sex, it can be very isolating if your feelings about boys (or girls) are the same as when you were 10. And then that continues into your 20s, and all you're interested in is platonic friendships. Yes, it is as isolating as being autistic and functioning in society - functioning as an outsider always second-guessing yourself and trying to fit in.
I've known several people tell about receiving adult diagnoses of ADHD, ASD, and dyslexia. Without exception they said things like "I'm not stupid after all!" Because when you cannot fit in, cannot do what everyone else seems to find so easy, so natural, you tend to get labelled stupid, and you tend to internalise that label.
We've seen it here on MN, when posters discover that other people are also asexual - they are not defective, they are OK! Equally, for that young person who feels something is wrong with them when everyone else is pairing off, to discover, "Oh, it's not just straight/gay/bi... it's straight/gay/bi/ace, and I'm ace! I do have a sexuality, just like everybody else! I'm not stupid after all!"
That's what I mean by personally validating.
It becomes a problem when the personal is made public and is imposed upon others. It also becomes a problem when the young person who has embraced the label, then continues sexual maturation and begins to experience sexual feelings. That's when the current fixation with labelling becomes toxic for them, because they have internalised a temporary condition as permanent.
The navel gazers are the people who redefine terms in order to fit their own narrative, and justify imposing them on others. Eg monogamous with low sex-drive=asexual=queer=oppressed=need for public validation. That's the navel-gazing drivel.