Well, “the system of your choice” could very well be one you design to fit the world, and I do quite strongly believe in system and setting and style of play all fitting together (though I’m seldom a big “design a system from scratch” sort of designer, with a couple of exceptions I’m quite pleased with).

The question’s also a reaction to a lot of fantasy worlds built thoroughly from D&Dish assumptions without questioning them. Indeed, that’s the overwhelming majority I see in RPGland and I find that quite depressing.

For example, I lost interest in Fria Ligan’s last fantasy Kickstarter when they started talking about elves and dwarves, but the depressing thing to me was the number of backers wanting that. Or the first PbtA fantasy game being the PbtA take on D&D. I want worlds outside D&D assumptions; preferably the majority of them.