I don't think I follow your concerns. For styling, there has never been a requirement (or even, really, an incentive) to style your elements directly in JSX. I

I don't think I follow your concerns. For styling, there has never been a requirement (or even, really, an incentive) to style your elements directly in JSX. It's possible to do so but you're just passing through inline styles to HTML. For "the province of the designer," do you mean the designers of your sites are writing all the HTML and CSS themselves? I do not think that's the province of the designer personally, but it may be an older school of thought (I only started my career in the age of React). When writing in JSX, they truly can become thoroughly intertwined, as the structure influences the styling and vice-versa, and code can control either of those other options. I find this complex, but quite reasonable. The majority of the time it's actually just straightforward.