FFS
I don't really understand how these perfectly serviceable terms become verboten. I suppose it happens organically. But as people have pointed out up-thread, there IS a difference between having Special Needs and having Special Educational Needs. Theoretically, to cover all bases, we say SEND (Special Educational Needs and (or is it, Or) Disability.
My son has severe ASD (or is severely affected by his ASD. Hey! I actually don't care which of those framings you use, and I interchange between them myself). He is largely non-verbal, not wholly continent, has a whole raft of sensory issues and behavioural 'quirks' and melts down reasonably frequently, often for reasons we cannot fathom.
He has special needs. He also has special educational needs (and a diagnosis and EHCP to support and verify that). I honestly do not care if you say he has either Special Needs, Special Educational Needs or SEN, as long as you make an effort to understand his challenges and approach him with an open mind. And also be prepared to love him, because he is utterly wonderful and very lovable.
If I overheard you, in a playground for instance, saying snidely 'he's a bit ... Special' I would probably march over and give you a piece of my mind. And a bit of reeducation.
Nuance, people. Social interaction is based on subtleties, one reason among many that people on the spectrum can find social interaction so fucking hard.