What makes you think people wouldn't have done this if they had the opportunity? These things are much higher in modern times because we have the capability to do so. What makes you think that if the technology was around then, or if people from that period were bought into ours, they'd act any differently?
Squandering of natural resources are not new things, see for example Iceland or Easter Island.
Possibly. But your "What If's" don't fit the required standards of having
Empirical Measurements.
And the years 300 to 1200 AD for the ecological disasters of Iceland and Easter Island don't represent the mythical Cave-Man we are commenting on. They would be lumped in with "Modern Man" and serve to illustrate my point well that Modern men are dunces. Female readers. I'm sure, know this already.
There are other negative modern civilization "Empirical" indicators:
Urban Sprawl in a U.S. Metropolitan Area
Way to Measure Your Body Fat
Consumption, saving and investment are core variable components in the economy
Yet, originally, when civilization was founded:
15 The Lord God took the man and put him in the garden of Eden to work it and keep it.
Early man was of "Sharper" intellect than modern man:
19 Now out of the ground the Lord God had formed
[6] every beast of the field and every bird of the heavens and brought them to the man to see what he would call them. And whatever the man called every living creature, that was its name. 20 The man gave names to all livestock and to the birds of the heavens and to every beast of the field.
Though Man still made bad decisions:
"cursed is the ground because of you;
in pain you shall eat of it all the days of your life;
18 thorns and thistles it shall bring forth for you;
and you shall eat the plants of the field.
19 By the sweat of your face
you shall eat bread..."