In a book I read, I think it was "Stumbling on Happiness" he quotes a study saying that rich people were neither more nor less happy than average people. Poor people on the other hand were less happy. So having a villa and three cars, doesn't make you any more happy than just having a normal flat and a nice bicycle.
It makes sense though. If you have to worry about every penny, and how you're going to pay next months rent or get enough money to buy food. It's not particularly fun. I've tried it for a couple of months.
On the other hand, I don't see the direct connection between productivity and happiness. Being productive, doesn't automatically make you happy. Having achieved something important through productivity surely can make you happy, but you can also be an extremely productive and be miserable, like a working drone at some company.
Once I lived in a tent for two months. I began each day by going swimming in the ocean and eating breakfast on nearby cliffs. Afterwards I would go into town to work. It was a really nice time, even though I was living on an extremely low budget.
To me I find happiness comes from working on fulfilling projects, something that's meaningful to me and feels significant. And from simplicity and focus.