I've poked at web components on and off over the years and never been satisfied with them, but it was only recently that I took the time to put my finger on what exactly my fundamental problem with them was - I never saw any examples where data was being injected in the way you do when working with React/Vue/etc.
https://jsplumbtoolkit.com/blog/2024/07/18/wrapping-data-in-...
Once I introduced a basic mechanism for injecting data it all seemed to be a lot more useful.