I mean, just a random quote:

"We never demanded the one payment that the world owed us—and we let our best reward go to the worst of men. The error was made centuries ago, it was made by Sebastian d'Anconia, by Nat Taggart, by every man who fed the world and received no thanks in return. You don't know what is right any longer? Dagny, this is not a battle over material goods. It's a moral crisis, the greatest the world has ever faced and the last. Our age is the climax of centuries of evil. We must put an end to it, once and for all, or perish—we, the men of the mind. It was our own guilt. We produced the wealth of the world—but we let our enemies write its moral code."
p. 619 ; Francisco d'Anconia to Dagny Taggart

Doesn’t that sound like real, actual humans communicating, and not just cardboard cutouts created solely for the purpose of robotically spouting Rand’s philosophy? It sounds almost like Rand had, at some point in her life, talked to real, actual human beings and learned to mimic their manner of communication, and to me this verisimilitude is the hallmark of truly great literature.