I listened to this piece, and thought it was interesting, but I got a somewhat different message from it than you do, because I didn't think that it suggested that not spending money on luxuries was what made people unhappy.
It pointed out that people have a pretty much set level of happiness, and it's hard to bump that. Buying a fancy car doesn't do much in the long run to move that level, but paying someone to clean the bathroom if you are very busy does have a modest effect on your happiness.
I personally am happiest when I am not too busy to clean the bathroom, but YMMV.