Discoveries will always be made altering the best efforts of scientists to project reality, past and present. The type of hubris in that general profession (science) is reinforced by colleagues and may convey a sense of security. And those seeking further are ofter shunned by their colleagues, creating a disincentive for thinking and exploring outside the box.
Think about the assumption that we are the most advanced conscious entities ever to in habit the earth. And what a threat it would be to discover evidence of an advanced race inhabiting our (really not "our" ) planet millions of years ago.

I couldn’t get the link to work but I know about these settlements from my readings. It’s amazing what smallpox did to the continent.

The Americas were well populated well and had thriving metropolises before Europeans ever got here.

Some people do not need us, the destroyers of their world. They were not in any hurry to let us know they were there.

Waaaa. I wanted to read it, but I must've already read some Washington post articles this month. I have to subscribe in order to read it.