So where is the booming community of CSS styles for popular websites, so that I can just change the way they look how I wish? Surely making one for Facebook would be no issue, right?

This would certainly be possible if developers/corps weren’t absolutely gaga for piling up complexity and ceaselessly changing shit for the hell of it. Facebook could and should serve stable, semantic HTML instead of javascript-ridden, ever-changing div soup. It wouldn’t make their development work any harder. In fact it would probably make it easier.

Unfortunately, in capitalism that’s too much to ask, because it would improve everyone’s lives except the ad industry’s.

Perhaps some sites can be excused from this because they really do fall on the app side of the document–app spectrum. Google Maps comes to mind, but Facebook? They’re just bad internet citizens.

I’m more on HTMX’s side of this discourse, but even going all-in on Separation Of Concerns one can’t ignore that different concerns doesn’t mean siloing everything off from each other. There must be interfaces/contracts between concerns and CSS Zen Garden teaches us one such interface: the markup. As long as it’s stable, you can separate styling concerns from it. Bonus points if it’s also sane and semantic.

CSS was brand new. It was a showcase to show a generation of web developers who used HTML tables for layout (probably using Dreamweaver) how CSS and semantic HTML could be used to achieve the same result, but with readable code. In some ways, component-based architectures are just a re-hashing of the old paradigms we worked out of.