"WHAT do you want to be?" vs "WHO do you want to be?"

Question

I came across this

What do you want to be when you grow up?
[...]
Are you right now who you want to be?

and the first sentence sounds weird to my English learner's ear. Specifically, I am questioning why what was used instead of who.

What do you want to be when you grow up?
Who do you want to be when you grow up?

I was taught that what usually doesn't refer to a human being.

Does it sound OK to you?
Is there any difference between the two?
Is there anything what puts emphasis on there?

The author is an American.

Answer 1

"What do you want to be when you grow up" refers to the profession (doctor, teacher...), not to the person, so it is correct and sounds just fine.

The search (in quotes) in Google: "What do you want to be when you grow up" gives 853,000 results, site:uk, 48,400 and site:edu 9,740 results.

"Who do you want to be when you grow up" refers to personal characteristics, so who do you want to be as a person.

What do you want to be when you grow up is also commonly used on more formal (.gov) sites, but Who do you want to be.." not really.