Often, this kind of gaming is referred to as "old school" or even "primitive" or "simplistic". And the truth is all three of those descriptions are accurate to some degree, but don't have to imply a negative connotation.
Dungeon delving is certainly old school. While i am a "middle schooler" who started with the Red Box, I discovered AD&D early and was enamored and inspired by Gygax's vision of the game, so i consider myself "old schoo" from a certain perspective. And while I ma sure there were plenty of narrativists and simulationists and what not even from the earliest days, the game started as just that -- a game of treasure hunting dungeon delvers seeking fortune and glory.
It's also a "primitive" way to play the game. or, more to the point, more "primitive" versions of the game support the playstyle better. Modern game design tends toward over-design, trying to cover every possible avenue, trying to serve as a generic Fantasy RolePlaying Game. When this happens, one of two things occurs -- either everything gets diluted so it does nothing well, or the rules get so vast and bloated that navigating them and parsing out just what serves the Dungeon Delve playstyle is nigh impossible. This isn't to say that a modern version of the game can't be used, but the existence of both Old School simulcra and new school retro-games like C&C and HMb shows that a focused design will serve a particular style of play better than a broad design.
Finally, there's the "simplistic" quality of dungeon delving. it's not that the play itself is simplistic, or that the dungeons are not complex and require a degree of skill to navigate. Rather, the simplistic theme of hunting fortune and glory within a deadly environment is a powerful tool for "finding the fun" as the kids say these days. Without a "plot" or a "boss fight" or any of that, the dungeon becomes the antagonist (with a little help from the DM) and each session is a chapter in an every evolving and expanding "story", without interference by would-be-novelist DMs or game designers. The tales to be told will be ones of valour and greed, terrible hilarity and stunning wonder.
Anyway -- there's nothing wrong with an "Adventure Path" or "Character Story" or "Campaign Theme". But by the ame token, there's nothing wrong with a good old fashioned dungeon delving campaign either, where levels 1 to whatever take you deeper into the depth, closer to glory and riches, and mere survival proves that you are a hero.