I can understand that. Most people do. I feel the same. I was much taller back home but it was not considered normal here so I was shorter when I arrived.

But new things can be disconcerting. I have been learning new things about the limitations of the human body first hand. It is not something that I would have thought that I would need to do and it was disconcerting. I did not have a choice in the decision, but if he does not understand it, he is making the decision to consider it more. Perhaps if you are able to find someone with his evolution, let the two of them talk. Maybe he can answer his questions first hand.