That's all RPGs, because they involve a table around which sit a group of players playing a game together. You've merely desccribed the concept of an RPG, wihtout addressing the ways hundreds of game have been designed to emulate different genres and experiences.
I know there are people who say D&D can mimic any genre. Sure, you can put a dress on D&D and say it's a cowboy, or a spaceman, and get a shallow facsimile thereof. But what's even better is a game designed around cowboys, or spacemen.
Look at some current Kickstarters, such as Darker Hue Studios' Haunted West. Sure, you can do that in D&D. But you can do it better in its own game.