is there anything similar for comparing work-life balance at different companies?

What are you thinking to compare WLB? Like a WLB score that folks can vote on?

One challenge is that WLB is more team specific than company specific as it can vary from team to team.

Try "The difference of man and the difference it makes", by Mortimer J. Adler

Or they do work, but you're doing it wrong: https://en.wikipedia.org/wiki/How_to_Read_a_Book