Define "Calling plays." Steve Grogan was the last QB to call his own plays. (That sounds very cerebral, but according to Terry Bradshaw that is like 6 pass plays and two 5 runs- left deep pass, left short pass, etc.)
Now every QB, including Peyton, gets an OC radioing him a play call. In his case (and Brady, and Brees, and Rodgers) it is like two passes and a run and he can change it based on what he "reads" of the defense. (It might vary, Brady gets 2 passes with 3 variational routes and Peyton gets 3 pass plays or whatever.)
Every QB can "audible" out of a play. Let me revise that; every "good" QB can audible out of a play. Let me revise that again; every QB trusted by his coaches can audible out of a play based on what he sees. (If the OC doesn't see it too, the QB will not be "trusted" for long.)
Sportscasters say that about Manning to justify their preconceived notion that Peyton is just plain better than any other QB ever.