In my mind, SCSS + CSS modules + maybe a processor tool is an rock solid and modern set of tech that produces excellent results and most importantly moves styling off the main thread. It makes sense to use it, but we don't. FE interviews even for senior+ roles are JS/React/system design questions. Nothing about CSS and I get it. Why interview for something you don't use internally?
I recently read something that stuck with me, which was about micro front ends but I think applies in more cases than this: "it doesn't solve a technical problem but an organizational one".
There was an excellent reddit discussion on the pros and cons of tailwind and it boiled down to "it's really hard to enforce CSS guidelines for teams of multiple people". Tech leads didn't want to monitor how 10 or 20 or 50+ different FE developers wrote CSS and opted for tailwind so that everyone wrote the same, even if that meant multiple inline classes pasted on each element. I find this reluctance to enforcing guidelines weird, considering at $WORK we have multiple confluence pages and internal documents about React and Javascript guidelines and I have seen similar documents in previous work places. Would it be really different to apply the same mental paradigm for CSS?
Of course, all this is under the hindsight knowledge that HTML and CSS have evolved in recent years to be truly powerful and versatile. I get the technical decision to go all in on JSS and React 5 years ago. I don't now.