The next step when thinking along those lines should be to remember that linearity plays only a temporary role in nature, until some threshold is reached of one

The next step when thinking along those lines should be to remember that linearity plays only a temporary role in nature, until some threshold is reached of one or many developments, and things change. A look at the historic human population numbers on this planet, which exploded to unseen heights only very recently (200 years or so), coupled with looking at the also vastly increased impact of every single person compared to far more spartan living ancient humans, might give one some ideas that extending past trends might be an especially bad idea in our times. Sure, we as a species lived through a lot for hundreds of thousands of years - but none of that past is of much use to predict our future.