Superman is tough enough to require Thanos grab hold of him, pummel him. like with Surfer, Thanos really shouldn't be having an easy time of it, it should be - at the least - like a man trying to catch a mouse... darting about all over the place, tight and unpredictable changes in direction ...
Superman's H-V and breath might also help slow down or at least push Thanos back... whilst Hulk would simply murder Thanos the second it becomes hand-to-hand.
Thanos has never in his history done anything to prove that he would pose the remotest of physical challenges for current Hulk.
I like Thanos a lot, but he's no serious competition without prep/tech/exotic powers. maybe if he demonstrated the ability to drain Hulk's gamma... well no, not even then (see how Rulk did with that?).