Hi Rufus
i wrote that the 747 was the world’s most significant jetliner, since it is said it has carried 3.5 billion passengers. Equal to more than half the world’s population.
I’m not aware of any other aircraft that comes close to that.
Being in production for 50 years, also means it has been with us for almost half the period since the Wright brothers first took flight at Kittyhawk. It will continue for many years yet.
So to me, the claim looks pretty straightforward to support.