The hover problem does kind of suck--- as far as I know, Radium (and others https://github.com/FormidableLabs/radium/tree/master/docs/co...) tend to solve it by wrapping components with a component that tracks hover state. And moving the hover-state tracking into React isn't the _worst_ thing--- JS is meant to be in command of the interactive portions of websites, so it does kind of make sense. If your :hover is ever going to have to do more, like show or hide content, it'll have to be in JS anyway.

The "JS Fatigue" haters will be cobolt-maintence programmers of the 2020's, I don't pay much attention to them. Javascript has a lot of churn because we have a difficult platform & language to improve upon.