I'm probably going to catch heat for this, because people (I did too, I won't lie) have a visceral reaction to the Javascript for styling, but... StyleX.
It came on my radar a few months ago when I first started noticing this rot problem. Then recently I saw that it was getting quite hyped and people have been singing its praise for solving this exact problem. So I'm giving it a shot.
Can't say for certain whether it will work out well or not yet, but based on the feedback I've been seeing from others, I'm hopeful.
i.e. https://dev.to/adioof/stylex-won-css-in-js-because-ai-agents... (not my blog).
That blog is obvious AI slop.
For us we went with CSS modules, it just made more sense for us to stay closer to web fundamentals since our styles are used across different tech stacks. From my experience in the last year, AI is quite good at sticking to your css ground rules and gleaning css patterns from other files all while being underpinned by design tokens (can have linters raise raw values to question also). Gotta use whatever works best for the job!