The post expresses no opinion on whether placing Tailwind class names directly on the HTML tags is better or worse than placing them in CSS. It’s merely saying

The post expresses no opinion on whether placing Tailwind class names directly on the HTML tags is better or worse than placing them in CSS. It’s merely saying that the mini-language of Tailwind class names themselves (regardless of where they are placed) is a new syntactic dimension compared to unstyled HTML—in the same way that CSS is a new syntactic dimension compared to unstyled HTML.