2D stereo is all about the equipment. We have two ears, headphones have two speakers and cars have two sides (I realize there are often 4 speakers in a car, but the layout impedes the sounds). Considering so few people consume music at home in a high quality setup, but rather on the go with low quality equipment, I don't see that changing. Interesting that the long running debate about Beatles in stereo vs. mono is centered largely around the fact that the music was mixed to be listened to on a mono phonograph speaker that most people had. As far as we've come, low quality is still how music is delivered.

There are some good DVD-A or SACD's with 5.1 audio, but they are niche and expensive.