Do all melee attacks deal the same amount of damage?
With one exception, all quick melee attacks performed with the V key deal 30 damage and have the same hitbox. When playing as Brigitte, pressing V will swing her main weapon instead.
Some melee attacks, however, are their own weapons: Reinhardt's hammer deals 75 damage, Torbjorn's hammer deals 55 damage, Brigitte's flail deals 35 damage, Winston's attacks during Primal Rage deal 40 damage, and Genji's Dragonblade deals 120 damage.