Game Theory / MatPat - Doubly so if that's the only thing they'll believe, regardless of how much canon information you show them.

Game Theory is just “What level of bullshit can I get away with this week?”
His evidence is paper thin and doubtful at best. That whole “Pyro is a gay man” theory relied on finger length as evidence and yet this is a cartoon game with completely disproportionate bodies.
Hoovy’s hand is bigger than scout’s head. What does that say about realism?

PEACH IZ TOTALLY ROSALINA'S MOM U GAIZ
Never living that one down…