Sorry for the delayed answer.

I think we're disagreeing on the definition of a "person". I'm using the word to refer to a mind and its subjective experiences inside its own head. You're using the word to refer to a body and other people's relationships with a mind. It's internal vs external.

Yes. You're right. However, I would argue that there isn't such thing as a "mind and it's subjective experiences inside it's own head" without a social reality supporting it. You're coming from a Descartian point of view, and I'm going through a Hegelian one.

This is not dehumanizing high support needs disabled people who can't communicate effectively, but pointing out that they are still part of our world, and we're part of theirs. Even if neither us and them recognize that.

As you say, consensus reality is a social construct. If someone is not socially impressionable enough to be taught this construct, then they are not a member of reality.

That's where I hard disagree beyond philosophy. Because it doesn't matter if You don't understand or recognize a social construct, it will still affect you and produce reactions, ingraining itself in you. As long as someone can experience anything at all in this world, they will experience the consequences of social decisions, and by consequence, a mirror of decisions made by this society. And as long a someone can produce any behavior at all (save reflex), they can and will communicate.

This consciousness is always imperfect even with NTs, but it's always there.