There are (or were) some witty American programs, but they're few and far between. As a kid I used to scour the fall TV Guide to see what was coming up in the new season, now I rarely watch live TV, it's usually just PBS for news and their programming. Several that ended a number of years ago include Elementary (there are some great one liners in there), on streaming Only Murders In the Building, and a few other mystery type programs. PBS just finished replaying the Sherlock series (Cumberbatch), and with the exception of the last agonizing episode, it was wonderful. I've read most of the Doyle Sherlock stories, but I didn't have any point of reference for that last episode. (Did anyone else?) Doyle is fiction but that episode seemed to stray into a fantasy realm.

I have yet to read any LeGuin, but I know she is very highly regarded. It's the old "there are only so many hours in the day" conundrum.

In 1970 there was a film made called Colossus: The Forbin Project. I heard about it, but back then there was no film on demand, no Blockbuster for VHS, etc., so I found the book Colossus by D.F. Jones. (From 1966; it was about an AI computer - see where this is going?) I did eventually see the film (a long time ago also, but I did order a copy I have here on DVD I need to watch again.) It's so long since I read the book I don't remember how it varied from the film, but both were excellent. And I see on GoodReads that there were three novels by Jones about Colossus and I've only read the first.

H.G. Wells War of the Worlds is a story told and retold many times. On the radio by Orson Wells with remarkable results; I haven't seen all of the versions but I particularly liked the Gene Barry version from 1953 (his sidekick was a librarian, and that actress could scream - that may be why she got the role.) And the more recent telling in Independence Day.   

One author you may not have thought of for fantasy, or at least dystopian fiction, is Louise Erdrich. She had one novel Future Home of the Living God that never said why the events were happening, but made the whole thing creepily plausible. That's a novel that stuck with me, I find myself considering aspects of it fairly often.