Reading can't have been always foundational. Most people couldn't read a few hundred years ago(according to practically any source ever). The printing press has

Reading can't have been always foundational. Most people couldn't read a few hundred years ago(according to practically any source ever). The printing press has been around less than a thousand years. Paper has only been around a few thousand years or something. Ancient Egypt is like 5 thousand years ago. The agricultural revolution is like 10 thousand years ago and the foundational skills would have changed from running, hunting, foraging to planning out fields, strength and other farming skills.Best guess is that humans have been around 100 thousand years give or take. What is foundational changes over time and depends on what skills you are trying to build. Given math and reading have only become foundational recently, there is no reason to think the skills considered to be foundational won't continue to evolve.