Is CSS that awesome? It's still a language designed for styling webpages with 30 year of added features. I'd argue something purpose built would be a much better tool for the potential usecases people try to use CSS for now. I guess I am asking, if modern CSS is so awesome, it's awesome compared to what exactly?
What kind of system would you propose (or do you envision) for applying visual styling to HTML markup in modern web pages today? You can keep it high level but your comment makes me think you have something in mind, and I'm honestly curious.
In CSS on the web, just centering a div has historically been a problem. We have flexbox now, but what if CSS was designed with our current needs from the get-go?