Oh, I get that perspective, too. There's actually a lot of overlap between the two, IMHO/X, especially when the imagined world is based on fiction or a genre of fiction using tropes from that genre (often very selectively).See, I don't think about TTRPGs in terms of stories or tropes, but rather in terms of an imaginary world the players explore through their PCs. Creating that world, arbitration disputes, and resolving outcomes is what I'm there for. How the players play and what they decide is up to them.
I sometimes feel like games, especially old-school games or games ostensibly trying to cater to the "explore imagined world" theme, end up with just the overlap portion, or with some mechanics they don't need/shouldn't have.
In recent years (OK, decades) the storytelling paradigm has been explored by, well, Storyteller in the 90s, and indie games, quite a bit. Some games have gone very far into mechanics to support that approach. I mentioned Leverage, above, there's even a Leverage RPG with flashback rules.
But, if you're exploring the imagined world through your character, then your character's senses, physical capabilities, and supernatural powers matter. But, it's your knowledge, memory, cunning, puzzle-solving and decision making that matter. Like, if I were to take 1e, and use variants to push it in that direction, I'd convert INT to like "Magical Aptitude" for MU/illusionists, WIS to "Faith" for Clerics/Druids, and CHA to, IDK, something else... ... not Comeliness, maybe "Destiny" or "Magnatism." The idea being to leave intelligence, common sense, puzzle-solving, persuasiveness &c to the player.
In in-fiction rationale? Well, "isekai" I guess - though the convention of a reader-identificantion character mentally jumping into the life of a fantasy character is older than that.