Anyone who studies with humility and intelligence comes to understand that what we "know" is very much dictated by who is in charge. Who is in charge is relative to what sphere of influence, and they overlap: Politics, religion, education, science...

There are lots of ancient structures being found now in deserts and jungles with technology that did not exist 30 years ago.

These new discoveries do not fit with what is "known" therefore they will be discounted until the framework of what is allowed to be "known" changes.