I think the problem is that the standard keeps going up and players expect it now. In the old days the module maps and art was so much simpler and that was considered neat and good at the time. As a DM on many years ago my pencil sketches were worse than even the old school maps.

Fortunately we have better tools to make better maps now. Its probably faster to make an old school map at the old standard now than it is to make rough one with a pencil.

Even over the last year the challenge entry standard here is going up. You now have to have photo textures and lighting with shadows and maybe 3D with cutaway views and perspective etc etc.

With Halo and Oblivion the target is the gamer not the mapping nut. The worlds must be in 3D which is much harder than 2D. They are designed and balanced for a good shoot up or hack up not for telling a story. There's extra limitations for the game engine and the capabilities of the console too. Halo is a great example where the cliffs tend to be either about 10ft or 10miles high and nothing in between. But as a player knowing whether you will survive if you jump off one is more important than the realism of it. I thought most of the maps in Halo for the story, as opposed to the squad battle maps, were really good tho.