These thoughts are certainly not new. Classic books appeared during the seventies with the publication of the Club of Rome's 1972 book Limits to Growth. However, what captured the public imagination more was E.E. Schumacher's Small is Beautiful which came out a year after. Aside from reiterating the unsustainability of much of modern life, he also champions downscaling resource use and obviously the modern preoccupation with "bigger is better" which often encourages wanton exploitation of finite resources.
Although the presentation style of the short clip above from the Post Carbon Institute may not be to everyone's liking, I suspect that the general message does resonate about oversized expectations that have in no small part yielded outsized rapaciousness especially among those responsible for the global financial crisis.. Moreover, it is encouraging that mainstream economists are starting to realize that proper valuation of natural resources makes perfect economic sense and that doing so is becoming a mainstream viewpoint.
So yes, I do believe that scaling down and moderating expectations have their place in modern life. However, I am not nearly as much of a hair shirt enthusiast as some of the more extreme environmentalists. If conservation and reuse are possible, then compromises need not be so drastic.