Exactly what it says on the tin – the Forgotten Realms is clearly principally inspired by romantic fantasy, not high fantasy.
In this context, when I say "romantic fantasy", I'm referring to a specific, relatively short-lived genre of fantasy literature that was wildly popular in the 1980s and 1990s, but abruptly fell almost entirely off the map after about 1998, due to a variety of economic and cultural factors which are way too complicated to go into in a Tumblr post. This is distinct from the more contemporary usage of "romance novels with fantasy settings", though there's definitely a lot of overlap.
If you're looking for a romantic fantasy reading list, Mercedes Lackey's Valdemar series – especially the early stuff – is probably the easiest to get your hands on these days; it's practically the only example that still has any real name recognition in 2025, for all that Lackey was a latecomer to the genre. Other names worth checking out include Margaret Ball, Carole Nelson Douglas, Tanya Huff, Holly Lisle, Jennifer Roberson, and Elizabeth Ann Scarborough, off the top of my head, though not all of them worked exclusively within the genre.
(Elizabeth Moon is an interesting edge case, in that her stuff is principally military science fiction, but very much adheres to the forms of romantic fantasy. Her Deed of Paksenarrion trilogy, one of her few pure fantasy works, is a fun snapshot of an era because it was written explicitly in response to what Moon perceived as the shortcomings of the fantasy worldbuilding on display in then-contemporary Dungeons & Dragons settings, and hit the shelves at just about exactly the same time as the earliest Forgotten Realms material.)