It's important to master plain old HTML and CSS. It's the unchanging foundation of every web framework. No one markets building sites with vanilla HTML and CSS,

It's important to master plain old HTML and CSS. It's the unchanging foundation of every web framework. No one markets building sites with vanilla HTML and CSS, which is precisely why I think it should have more weight in people's curriculums. You don't need a React <Button/>. You can use <button> and CSS "appearance" to style it.