Dealer says new cars don't need protection, is that true?

Picking up a brand new car next week and the dealer told me not to bother with paint protection because "new paint is already protected from the factory." That sounded reasonable at the time but now I'm not so sure. My last car was a few years old when I got it and the paint was already tired, so I've never actually owned a new one and don't know what's normal. I read a Quality explanation of why new cars need paint protection and it made a fairly convincing case that factory protection isn't the same as real protection, especially in this climate. But I'd rather hear from people who've bought new here. Did you protect yours straight away or leave it? And did you regret either choice?