DY: I think contemporary people (especially Chassidim) apply Sod Hashem Lireiav to Gedolim today. But that’s not relevant. I think you need to prove that Sod Hashem Lireiav means they know everything. As far as I know, the Gemara only brings it up in applications where it’s relevant Halachah L’ma’aseh. In those cases they knew advanced sciences. And even then we still sometimes have to say Nishtaneh Hateva. Once again, it’s arrogant and idiotic to search out places or try to attempt to prove Chazal wrong. But I don’t think there’s any harm in acknowledging that at times they listened to the scientists of their day, who could be wrong (see the Machloksim between the Chachamim and the scientists in Pesachim 93ish, I think).
Derech Agav, I had a Rebbe in 8th grade who said it’s Apikorsus to say that Rishonim made a mistake. He did not remain my Rebbe very long after I forced him to admit that he held that the Earth was flat in the times of Rashi, round when the Ba’al Hama’or said it’s round, and flat again in the times of the Rashba.
Also, I have always thought that the Machlokes in the Gemara Megillah 7a, as to whether Hodu and Kush were on opposite ends of the earth or next to each other was a Machlokes as to whether the earth is flat or round.