people just don't like the character, that's about all it boils down to.
Hulk's feats are too high for most peoples liking, the idea that this character who normally goes about running away from the military and/or smashing up mountains is stronger (and more innately powerful) than Gods (Thor et al), flying bricks (Gladiator et al) and assorted monsters (Onslaught, X-Men etc), only makes him that much more unpalateable... he doesn't have a majestic arc like say Surfer, where he's tangled up in the wonders of the universe and looking face to face with creator/destroyer types ... he doesn't bring to life a mythos like Thor does ... he just exists to be annoyingly - incredibly - powerful and without true purpose.
Hulk destroyed technology designed to ward off Celestials, that was dismissed as meaningless.
Hulk contained and then released (without any damage to himself) 2 universes of energy - which in anyother case would be taken to mean enduring a "Big Bang" - but that is totally ignored when talking of his stamina, durability and capacity to take punishment/energy attacks (ie, so and so should "overpower him", such and such an attack would "kill him" ...)
I just think the character lacks the kind of purposive stories that drag alot of the more fanatical crowd to comics. you can't really look up to Hulk, he's just a very human man, with Godlike (more in the league of Beyonder than Odin) power ... more afraid of what he could wrought than with bringing the universe to some superior order or defending the order that already exists (Thor and Surfer).
think about it, Beyonder says Hulk's power is like his own, in magnitute (infinite), Galactus can feed off of "The Old Power" and be sustained for a thousand years, yet The Old Power is miniscule in comparison to the power exhibited by a weaker Hulk ...
if you swapped Hulk's high-end feats with say, Thor's, everybody would think Thor was truly a Skyfather... not many would be upset at the ridiculousness of those powers - because they would have a narrative purpose...
Hulk's stories are more psychological than narrative focused... they're about coming to terms with yourself, with your capabilities and desires... in their totality and about the consequences of not doing so, imo.