A car that has fewer features available is decontented in comparison to one that does.
The 2012 Passat is a new model with an old name so there can be no decontenting. If the 2013 has less features than that would be considered "Decontented". We will see next year.
The Passat back in 2007 was available with xenon in the high trim as far as I know. Rear vents are hardly a new thing, although VW could take a hint from Hyundai, since that company's vents are better. LEDs have been available in some VWs like the Toureg for a while as far as I know, but the fact is is that the B7 Passat for China has them. History is interesting, but we're living in the present.
And what was the price of that Diesel 2007 Passat with xenon lights in 2007? I am sure if the new Passat sold for the same price they could afford to throw in the xenons.
Ride in the back seat of a black/black Leatherette Passat in 95 degree heat after the car has been sitting in the parking lot. It's not "fascination". It's a matter of simple physics. In order to cool the rear area, air has to get from the front of the car to the rear of the car. Without rear vents that push a decent amount of air, less directional (more diffuse) air has to be moved from the front vents, which creates more noise and takes longer to cool down the back. It also makes the front colder, possibly, than the people in the front want, in order to get enough coolness to the back.
Well I think the first thing one would do is get the hot air out via the sun roof or side windows than the forward air vents will do a fine job of cooling the car. It is not a huge SUV type space we are talking about. The rear vents in my 2009 JSW would have a hard time blowing out a candle.
What is fascinating is that China is considered a market in which it's appropriate to offer extra features like xenons, LEDs, and rear vents, while the US is not.