Obviously mapping isn't required for a game, and I certainly wouldn't force it upon players who had no interest in mapping. IMO It's more like miniatures rather than dice: you don't need minis to play the game (even in 3.x), but many people find it a more enjoyable experience playing with minis, and painting them flexes some fun creative muscles; dice OTOH, are more of a hard-requirement to enjoy the game---you can certainly play D&D without dice via chits or spinners or a random number generator on a PC, but using dice enhances the experience of playing D&D.
That said, as various folks have aptly raised, mapping in the game is likely one of those generational things in D&D: if you grew up mapping and liked it (plenty of folks didn't, even back in the day), it's a fun part of the experience of being a player in a D&D game. I.e., it's not about whether or not the PCs have any proper mapping materials, or whether the PCs have a 24 intelligence, or direction sense, or whatever: its something that adds (or subtracts) to the play experience of the player, and that is why, IMO, so many people hate mapping so vehemently: it's not because it's not logical for a PC to map well or not based on his stats, it's because the player simply doesn't enjoy it.*
* I also think that DM skills at providing easy mapping descriptions are something that takes practice to do well, and DMs who can't describe the game so that players can map it easily would make the mapping experience pretty horrific.