Romcoms have been showing stalker-ish behaviour as romantic grand displays forever and whilst people having been calling it out for a while I would say that it's only really in the last few years that they've stopped putting it in movies. So whilst it is problematic Mikey and Steve's relationship is very much a gay version of an existing trope.
Life After Life I read and enjoyed. I remember feeling like I kept hoping there would be a point, but if there was I missed it. Well written though.
The Man in the High Castle Dick was one of those authors I was embarrassed never to have read given how many movies based on his work I've seen. When I finally read this I was so disappointed and nearly threw the book (it was a paper copy) across the room. The world building was well done but then nothing happens. Again I felt like there was a point I was missing.
I'm trying to think of other examples. A long time ago I started reading
West of Eden which is the first of a trilogy set in a world where dinosaurs never died out but evolved into intelligent bipeds and became the dominant species. It was OK but I found it a bit of a slog and never finished it.
Jonathon Strange and Mr. Norrell is set in an alternate nineteenth century where magic is real. Does this count as AU? I think so because if you take all those fantasy books where magic is real in "our" world then mostly it's secret or hidden or known only to a few. In this magic is acknowledged publicly if only practised by a few.
Dominion is a book set in a world where Britain surrendered to Hitler. I only got a few chapters in but it seemed well written. I will probably get back to it at some point.
The Ragged Astronauts, one of my favourite books, is set in a world where pi is 3. Actually this has no bearing on the story as such, and it's just mentioned in passing. The story is set on a pair of planets that share an atmosphere and concerns a migration from one to the other using hot air balloons. I suspect the author threw in the pi detail as a cheeky get-out clause in case anyone complained about the physics of it all.
I've got
Funny Girl listed in my Goodreads 'alternate history' shelf. It concerns the rise of a "British Lucille Ball" character. Not sure it's really AU, except in the sense that all fiction is. But I think I shelved it as such because there simply was no similar figure at that time. A story of a 60s comedian who rose to TV stardom could be a fictional character but have lots of exemplars in real life. That said it was recognisably "our" 60s/70s/80s history otherwise.
The First Fifteen Lives of Harry August is a story of many alternative worlds as the main character lives his life over and over. This is more of a "what would you do differently if you knew..." kind of story. I found it very enjoyable.