Rant: Alien culture stories never grabbed me until I picked up this one book!
I always avoided sci-fi about alien societies because they seemed too dry. My friend shoved 'The Left Hand of Darkness' at me, and its ideas on gender completely pulled me in! Now I seek out all kinds of alien world tales, and it's so fun to see how creative they get!
Honestly the best ones mix both, like that book did. It uses a wild alien setup to explore basic human stuff in a new way. You gotta have that hook or nobody cares about the world building.