That position makes no sense, though. First, how would an act I perform as an adult (getting an Italian passport) change my status as "natural born"? Note the word "born" in there. Second, under Italian law, I'm already a citizen, even though I don't have a passport and they are, in fact, completely oblivious to my existence. Simply applying for a passport doesn't grant me citizenship--I already have it in their eyes.
You’ve an after birther for a long time. I’m not going to step it in with you, other than to say this:
If you (theoretically) consider yourself an Italian citizen enough to get an Italian passport, then you are not an NBC because of dual loyalties.
Someone born with NBC could lose it by becoming a citizen of another country.
It’s simple but people who want have ulterior motives on this topic bore me.