Why is that not a private email address? Just because I have a corporate email address, that doesn't mean I expect random fan mail or people I don't know emaili

Why is that not a private email address? Just because I have a corporate email address, that doesn't mean I expect random fan mail or people I don't know emailing me complaints/whatever. Twitter received a complaint from NBC, and according to the Terms of Service, the account had to be suspended. Obviously this backfired, but that's not the point.