My view on the whole 'this isn't an rpg statement': 1) I think these kinds of declarations aren't terribly useful, because usually people are using definition of RPG to advance a playstyle, so I think it is generally a bad argument. 2) But I don't think it is gatekeeping. It is, possibly, a bad faith argument, definitely not a good argument, but a person saying "This edition of this game isn't an RPG" isn't a form of gatekeeping. 3) Gatekeeping is actually pushing people out of the hobby. I think we throw that term around a lot, but by doing so you just water down its meaning. I would reserve gatekeeping to statements like "Girls shouldn't play D&D". If it is opened up to mean statements like "this isn't an RPG" then it really has no power as a term IMO. 4) If someone specifically tells you "No the game you are playing is not an RPG, I think that is a little more frustrating and annoying than if they say "This isn't an RPG to me". I still wouldn't consider it gatekeeping, but I could see how it would get under a persons skin more.