The definition of "luxury" is always changing. I would not trade places with Louis XIV. He can have his luxuries. I like mine. Real prices keep falling and availability keeps increasing. That's a lot of new consumer surplus. Consumer surplus is not measured by GDP or other conventional accounting. Those who beat the drums over increasing inequality should pause to notice the amazing "democratization of luxury."
It is interesting that the stagnationists (see Adam Davidson in today's NY Times mag) complain about slowing productivity growth but rarely mention the increasing availability of the goodies. Google trends shows that "digital divide" is cited less that it was ten years ago. Of course. Prices have come way down and access is better than ever for many more people.
We often hear that the 747 is so yesterday -- and we never got flying cars. But many more are able to fly. The latter strikes me as the more auspicious and the more interesting.
I found this just after I posted. There is lots of evidence on the same theme.