User blog comment:Kaido King of the Beasts/Chapter 908: Imminent, Imbalanced, Improbable Whims/@comment-24850639-20180615165048/@comment-24850639-20180615181814

You're right, but you gotta remember that knowledge was exclusive to Whitebeard. Even when Whitebeard said it out loud, he didn't specifically mention it having anything to do with the Will of D, so that's not the message people got.

What Whitebeard meant was, "You're not the 'D' that Roger is waiting for".

What people heard was, ".....the man Roger is waiting for....it isn't you".

So as far as the Marines, and anyone who is aware of the D. Lineage/Legend is concerned, Blackbeard isn't any less dangerous than Luffy, Ace, Roger, or Dragon are. In fact, Blackbeard has been proving he may be even more dangerous.