Hey, I am Thor fan too but he doesn't match the Hulk in strength and I think the movie shows it in the Arena, Hulk/Fenris, and the Hulk trying to tank Surtur but I think Thor more than outclasses him overall and it's only been the Hulk's dynamic strength that makes it the ultimate rivalry in Marvel.
I love both characters. The Hulk is a misunderstood monster, with a hero's heart but more of anti-hero.
Where Thor is the epitome of a hero, prince, top-tier power and one who others would follow into battle out of inspiration.
The Hulk has that unreal durability factor to go with his extreme strenght, so if the fight kept going on, would have been interesting!