CSS simply doesn't need a framework - there's no "from scratch". For humans or LLM authors.
Tailwind is a lot of overhead conceptually and tooling wise to just not have to write classnames, and it's actually anti-modular.
Can you explain? Tailwind massively reduces overhead for abstraction, classing, documentation, and maintenance.
That's not the full picture.
If you're a senior CSS developer you will invariably reach a point of using "object oriented CSS" which is where you combine classes to an effect.
At that point you're not far off Tailwind. TW just took it all the way.