Moderated registration won't stop Nazis, because they'll just pretend to be human to fool moderators, but it will stop normal people, who won't spend the effort to answer the application question or want to wait for approval.
on its face this is just an awful argument, like ???
99.9% of nazis won't even bother doing that... so it weeds out the vast majority of them
and that's what you have other moderation practices for!!