> Calculators reduced our capabilities in mental and pencil-paper arithmetic.

And now people make bad decisions in their daily life about money etc. Most people can't do the math in their head but they also aren't using their calculator at the grocery store to avoid being taken advantage of. The math doesn't get done.

The lesson isn't that we survived calculators, it's that they did dull us, and our general thinking and creativity are about to get likewise dulled.