To call something a “walking simulator” became not just a complaint about pacing but an existential fight for survival, spiraling to include larger and larger questions of who gets to be a gamer and what should be “counted” as a game (Chess and Shaw 2015). Real games are difficult, goes this argument: you can die in them; you can take “real” actions (i.e., shooting and loot collecting, not walking or investigating). Real game heroes are powerful and effective.
I think this belief arises from the stereotypical belief that games have to have winning situations or violence, while most walking simulators do not have winning situations or violence. I don't really agree with what people are saying about walking simulators because I believe walking simulators are games just like any other video games. As long as the player performs actions with a purpose, it can be a game.