What the fuck does walking simulator even mean? Is that term referring to games like Outlast and Amnesia? Even if it does that doesn't make any sense.
Originally it meant games like Dear Esther, Proteus, and Bientot l'ete, where walking was literally the only thing you could do and there are no typical fail states. Then people started applying it to games like Gone Home and Antichamber, even though those had actual puzzles, tighter level design and exploration (although the puzzle elements in Gone Home are very light). Although they still lack typical fail states. Before long people started applying it to everything that's first person and exploration-heavy, regardless of the existence of other gameplay elements. Now it essentially doubles as a blanket term for first person games people don't like, even if said game prominently features combat, platforming, puzzles, stealth, is a point and click adventure game in 3D form, etc.