I've been doing a bunch of reading recently into more 'narrative-first' TTRPGs. The moniker has never quite sat right for me -- I've always had the sense that people were never quite happy with how to refer to them and set them against other offerings in the TTRPG space. So: I'm talking about your PbtA ('Powered by the Apocalypse') and FitD ('Forged in the Dark') type games, as opposed to the D&Ds of the world.
The term's never quite stuck for me in part because I have tended to run pretty narrative-heavy D&D games. It's still pretty accurate to call these other games 'narrative-first', in that that's where the bulk of the systems and mechanics -- where the game is directing its attention and where it's asking you to direct yours -- fall. But I've started thinking of them as 'fiction-first' games.
My nascent theory is that a game like D&D, rooted more in a wargaming/tabletop battle-gaming history, is focused on simulating [aspects of] the actions, characters, and environments of the world within a setting. The 'fiction-first' games are focused on simulating, well, the fiction, and so often take the form of a careful deconstruction of the tropes, structures, and story beats of the relevant genre, and then turn them into interesting and fun game mechanics.
To be clear: neither is strictly superior in what it's doing, but this is what's made it 'click' for me. Also, it turns out Monster of the Week is pretty much the exact TTRPG void I've been looking for (at least on paper).