There are two different things at play here, and most people on either side are not talking about what the other is I think.
4E does have a 'complete history' as it were, as the backdrop for their game. Bael Turath, Arkoshia, the Nerathi Empire etc. Those permeate the entire game in the background. All of the gods are directly tied into that history, the battle between the gods and primordials are tied into that history, the eladrin and the denizens of the feywild are tied into that history. It's a setting. The Points of Light setting. The same way 3E used Greyhawk. And to have the entire game itself (mechanics and fluff) tied into that presumed setting does make things 'less universal', and thus more difficult to extricate. And this is proven by the fact that they recreated the Realms and Eberron to add a lot of this PoL history and background into those settings too.
Now the other side of the coin are the people who (I believe) just want a set of basic gods to start with (rather than generic 'God of Light' / 'God of War'), and a starting town or area in the DMG in which to set their game (like the Nentir Vale was for 4E, or Saltmarsh was in 3.5s DMG2) This way players have a very basic 'campaign setting' at their disposal right at the beginning, rather than having to wait and buy some other setting WotC eventually decides to put out.
And there's no reason why you can't have it both ways. So long as you don't tie everything (fluff, mechanics and otherwise) within the game to this base setting you set up for the players in the DMG (and instead you tell them that this is just a sample area in which you could start a campaign), you can have 'example' gods and 'example' cosmology and an 'example' setting that people can use if they want to... but have no problem ignoring if they don't.
4E does have a 'complete history' as it were, as the backdrop for their game. Bael Turath, Arkoshia, the Nerathi Empire etc. Those permeate the entire game in the background. All of the gods are directly tied into that history, the battle between the gods and primordials are tied into that history, the eladrin and the denizens of the feywild are tied into that history. It's a setting. The Points of Light setting. The same way 3E used Greyhawk. And to have the entire game itself (mechanics and fluff) tied into that presumed setting does make things 'less universal', and thus more difficult to extricate. And this is proven by the fact that they recreated the Realms and Eberron to add a lot of this PoL history and background into those settings too.
Now the other side of the coin are the people who (I believe) just want a set of basic gods to start with (rather than generic 'God of Light' / 'God of War'), and a starting town or area in the DMG in which to set their game (like the Nentir Vale was for 4E, or Saltmarsh was in 3.5s DMG2) This way players have a very basic 'campaign setting' at their disposal right at the beginning, rather than having to wait and buy some other setting WotC eventually decides to put out.
And there's no reason why you can't have it both ways. So long as you don't tie everything (fluff, mechanics and otherwise) within the game to this base setting you set up for the players in the DMG (and instead you tell them that this is just a sample area in which you could start a campaign), you can have 'example' gods and 'example' cosmology and an 'example' setting that people can use if they want to... but have no problem ignoring if they don't.