One of the salient features of physical interaction between humans is that we all expect each other to be roughly the same size. Between you and the person you are talking to, there might be a height difference of as much as a factor of two, but just about never more than that, and usually much less.
We are not physically co-present with people with whom we are speaking on the phone, or texting, or exchanging email. Yet we still retain a mental picture of them as being more or less “human sized”.
But with the advent of ubiquitous mixed reality, there will be no intrinsic reason why people need to appear to each other at their natural scale. If you show up on my desk for a brief virtual chat, it might turn out to be convenient for me to see you as a miniature version of yourself, whilst I might appear to you as a giant version of myself against the sky.
Technically, there would be no impediment to this mode of interaction, and there might be some practical advantages. As a tiny person, you could show me a dance sequence, or a walk a path through a proposed architectural space. As a giant person, I could draw some choreography on your floor, or arrange some lights or cloud cover for you.
The more you think about it, the more different practical uses suggest themselves for people adopting asymmetric scales when interacting virtually. But would people accept such arrangements, on a social and psychological level?
My guess is yes. After all, you regularly go to movies where you see the faces of your favorite actors at enormously large scales. And when you turn on the TV, you see those same actors looking very small indeed.
So it would appear that you are already good at dealing with people who have been virtually rescaled. It’s just that soon they may be showing up as tiny people standing on your desk, or as giants, peering into your window.