You're exactly right. Spider-Man can beat Firelord and Juggernaut. Storm is strong enough to disperse Stardust. Black Panther can put SS in a hold he can't break out of. Squirrel Girl can beat Thanos. Cannonball beat Gladiator. I've seen them all happen. Marvel said so. So these characters must be stronger than the people they beat.
Because he whispered at Hulk, then walked away, back towards Attilan with his Queen. Then Hulk surprise attacked him.
He wouldn't scream with Medusa nearby.
He wouldn't scream so close to Attilan.
He for reasons unknown didn't use any of his other powers. Oh and Captain America can KO Hulk with his fists; let's not forget that.
Blackbolt was then paraded beaten on hologram, surely he was able to summon a moan. No? Obviously the Hulk had broken his belief in his voice being effective as well.