I believe you missed the author’s point. He’s NOT just saying that great ideas get refined as time passes.
He’s also saying that many people refuse to accept that fact. And that is not a “captain obvious” thing. Even today, many so-called educated people simply accept scientific principles without any question. “Settled science”, if you will.
That’s not what I got out of it. He’s not talking about the ignorant, lazy low information person, but society in general, that even the learned, wise ones somehow believe that we know everything, or that everything we “know” is the final word.
Obviously you don’t think so, neither do I, and neither does anyone I know. So who is he trying to enlighten with his profound observation?