I don’t think anyone would regard using Barbie’s name in the movie as a title drop.
The article does:
> Unsurprisingly, movies named after one of their characters have an average of 24.7 title drops, more than twice as much as the usual 10.3.
And this thread started exactly with the point of what the article considers title drops.
The article also highlights the interesting case of “movies named after a character with single title drops”. I’m willing to bet that in those movies, if the name is proffered late enough in the runtime, it may feel like a title drop because the the audience suddenly becomes aware the name had never been said before. When the name is said all the time or once but too early (so you’ll be primed to expect it more often) then the effect is bound to be lessened.