Is "who is it?" wrong 2006? We don't normally refer to a person as "it", especially when they can hear us say that.
It is polite to ask 'Who is this gentleman?' or 'What is this gentleman's name?'
what about "who is that?" same answer
asking about people like "who is ..." when we first meet them is not polite ofcourse but what's your opinion about these 3 options for conversation 2?:
-Who is it?
-Who is that?
-Who is he?
None of the above are polite to say in the presence of the person. But if you are looking at a picture of people with another person, you can ask 'Who is that?' about someone in the picture.
Who is that (man)(lady)(child)(person)?