Other than books and movies specifically written as tie-ins for Pathfinder, D&D, & games spun off from them, what are some good series to draw inspiration from that more or less match the tone, themes, and assumptions inherent to the 2e/5e rule sets?
Because in most fantasy fiction, magic is so rare that the story’s protagonists and antagonists pretty much encounter most of the world’s magic items and users in the course of the story. Meanwhile, Pathfinder and D&D treat mid-to-high-level items and spells like Gulfstream V private jets: rare, impressive, and only privately owned by extremely exceptional people, but not so rare that each one is a household name inscribed in folklore.
Almost any isekai/portal fantasy/litRPG series in the fantasy genre is going to be compatible with Pathfinder to some extent. That's a ton of web novels and subsequent Kindle/Audible publishings, and high magic is very common in order to provide some manner of progression.
You could probably even port over some of the conventions for use- distinguishing categories of people by the highest level of proficiency they have in something.
As QuidEst mentioned, there are lots of fantasy works, particularly from Japan, that are built on the foundations of prior RPGs (both video and tabletop). You're starting to see more of a similar thing getting published in the west too like Legends and Lattes which use the D&D adventurer experience as a backdrop. You can certainly find fanfics and other amateur works galore online as well.
As a side note, it's always a bit weird to me when people say things like "why is vancian casting the way it is? no other media has magic work like that" or "why can't I play [exact replica of a character from another franchise] in pathfinder?". It's like there's some assumption that it's bad to be built off of earlier versions of the same game and not whatever other media people develop independently.
