I’m also skeptical that the 21st century has made very many skills obsolete. Sure, calculators can multiply for us. But a fluency with multiplication and familiarity with its structure builds essential knowledge that students need to engage in more challenging problem solving. It’s easy for those with knowledge to underestimate the extent to which that knowledge makes higher-order reasoning possible, called the “curse of knowledge” by psychologists. I’m a big believer in content. The more people know, the better they are able to reason about new situations in the future.