This is untrue. You're just thinking of the Super Bowl when Mahomes was running for his life. That isn't normally how Mahomes plays. In the SB, he had no choice.At some point you do have to become more of a pocket passer who makes quick decisions, limits the amount of risky throws, picks up blitzes quickly or audibles out of them, and run a standard offense. People who know more about the Xs and Os might say that Mahomes already does this at an elite level, but watching him I find a lot of his success hinges on broken plays and relying on his athleticism.
His success hinges on the fact that he's a generational talent as a pocket passer who also happens to be one of the best of all time at improvising, too. He cannot improvise in this manner forever, but Mahomes is going to be just fine from the pocket. He's got a cannon.