Or...a CSS class? I think the point is that CSS already has the means for abstraction built right in. Using an application framework in order to abstract a list of styles adds unnecessary complexity that compounds upon itself.

Somebody writes a React component to abstract a button and its standard styles, and all seems simple enough. Then we need marketing styled buttons, and buttons that are anchor elements, and ones that are small and large, and inverted and with and without shadows because the design people insist, with icons, block width, pills, etc, etc. And you end up with a monstrosity component with all sorts of bespoke interface that everyone has to learn, when some cascading classes and plain HTML would have entirely sufficed.