> "Separate content and presentation (HTML/CSS)" The wrong thing was the one-to-one mapping of the content, presentation and business logic to some specific te

> "Separate content and presentation (HTML/CSS)" The wrong thing was the one-to-one mapping of the content, presentation and business logic to some specific technologies (them being HTML, CSS, JavaScript). That's why so many people got confused when they saw XML tags in React. OTOH, as you said, we usually need simpler rules. The moment people started to think that "now it's OK to put HTML in JS", we started seeing blog posts being written in React containers.