While there is much hashkafah that needs to be articulated in this thread, as that is what is really bothering people here, let me just make one brief point.
Our Avodas Hashem in this world is through hester panim. The RBSH hides himself and evidence of himself to give us bechira. If everybody would have Ruach Hakodesh, there would not really be any nisyonos. For example, if Avraham Avinu knew that there was a ram waiting for him all along, then what schar would he get for going through the motions of sacrificing Yitzchok?
Our job in this world is not to achieve Divine powers and communicate with the Divine. As we also learn from Avraham, our job is to do chesed. Gedolah hachnasas orchim yoser meikabalas pnei hashechinah.
Some of the motivation behind the people saying that gedolim know science better than evrybody else is to imply that our job is to separate ourselves from the entire world and smugly declare that we are smarter than all of you, and everything you do is worthless, and we don’t need you. We are special.
But in fact, Avraham was waiting outside his tent to greet people of all types, and was happy to serve even three idol-worshipping Yishmaelim. Our job as Jews is to be meurav im habrios and to be the world’s teachers of midos and chesed and kindness, not to shut everybody out of our lives. Every person and nation has a potential positive contribution to make to yishuv haolam from which we all benefit. We offer 70 korbanos on behalf of all the nations on Sukkos. Only at the end do we offer one for ourselves. We put ourselves last in keeping with anivus.