Seems we have two rival understandings of the OP's post, which depend partly on different stress of the key words.
1) I and Aurifex take it as "What man is a
man who does not make the world better". Paraphrasing: Given that someone is a man, I would expect him to make the world better. If he failed to do so, I wouldn't consider him a man at all.
2) Pacis Puella takes it as "
What man is a man who does not make the world better". Paraphrasing: it's hard to imagine the case of a man who does not make the world better. But if such a thing happened, I would consider him a an odd specimen of manliness."
Which words are redundant? In (1), I could happily write 'Who is a
man who...'. Because the first 'man' is less important than the second. In (2), it would be '
what man is someone who... ', because the second 'man' is less important than the first.
Simple solution: find out which way they actually say it in the movie.