You could probably make a poptarts are sandwiches alignment style thing out of this.
Basically, any video game with an explicit goal, or set of goals is just a puzzle game with extra steps.
What buttons do you push, when do you push them, what does this accomplish, how does that lead you to your end goal, etc.
You could even argue that multiplayer tactics constitute a puzzle, a more social puzzle.
Yes, this is reductive, but this is a dumb showerthoughts post.
Is Portal a… First Person Shooter with Puzzle Gameplay? A First Person Puzzle Game?
Is Elden Ring an extremely difficult Action RPG, or is it really just an easy Action RPG hiding behind an opaque and complex system of weapons and armor and enemy types and stats that becomes simple once a viable solution to the puzzle of stats and weapons becomes apparent after either reading a guide or just brute forcing through tens or hundreds of hours of bad solutions?
(For that matter, what even is an RPG?
Role Playing Game?
If that just means that you play a character, ie role, and it is an immersive and or compelling story and world, ok, thats a loooot of games.
Does it mean you can customize your character’s appearance or weapons or stat-build? Ok tons of non RPGs allow for that, and tons of classic RPGs do not allow you to alter your character’s appearance.
If it means you have the ability to put yourself into the game, make choices and do things differently in a way that meaningfully changes how the world of the game responds, then a whole lot of ‘RPGs’ are hardly RPGs at all, as many develop your character(s) as part of their story line to the point that many decisions presented seem entirely out of the established character’s likely responses, or give the player few if any impactful choices, having a mostly or entirely linear storyline.
By that metric most immersive sims are more RPG than many ‘RPGs’, anything with a branching storyline or highly reactive world is as well.)