it's larp if they:
say "I played the game"
say "When I played I did xyz"
claim to know about everything in a combat/shooter etc type of game
it's not larp if they:
know the lore/plot of the game
have seen all outcomes of the game
it's a story game/game not dependent on skill
amongst all the trash you will find gems (I had people asking me how I found out I was a lesbian and how to know if they were one and I had to go I'm 16 my experience is limited 😭😭)