> the mental overhead of something like styled components

I've outlined a number of ways in which it reduces mental overhead, for instance removing SASS-specific syntax, reusing existing JS code, throwing errors for missing styles.

> Why don't you just have one component per JS file and a stylesheet with the same name as the component in the same directory?

Code this atomic is quickly a mess.

> (1) super easy to configure

This is not true if you wish to gain many of the benefits I've outlined.

> none of the five advantages listed are exclusive to Styled Components, but every one of its disadvantages is.

Six and the presence of all six within one solution is something I haven't encountered elsewhere (not to say it doesn't exist). Also to say every disadvantage is exclusive to SC is simply untrue.