Mario RPG was my favorite (yes Im eating good right now). I like describing it as a toy, there are so many things to be done for no other reason than to have fun, enabled by the fact you're a platformer character in a 3D fantasy world. You cant jump onto the store's counter in other RPG's of the time, but you get to in this game, and you're rewarded with being scolded by the shopkeep. You can jump on all the NPC's, on wedding cake, pianos, hyperactive kids, all the beds, catapults. Jumping is often times your response to NPC dialogue.
Texture resolution isnt the same as screen space resolution, textures have to be wrapped around what might be complex, high surface area models. And dont forget how close you can get to things, where just a fraction of a whole model is filling your whole screen.
The option would still be nice but 4k textures do have an effect even on lower resolution screens.