I think the "It's not [Game]" statement, with no backup, should be grounds for trolling. It's an attempt to try and shut down the arguement and offers nothing to the debate.
I used to say "It's not [game]" at some topics before but I
think I also gave some form of explanation even if it was small.
(I'm not 100% sure and I can't check it out either because I can only look 200 posts back on my profile)
(So I'm not going to bother looking after them, let's just say I might have trolled with that argument once or twice myself.)
(But I have been cutting back on it though.)