If you watch from around the 1h22m mark, you will see that he conceeds there is no such thing as "energy conservation", and that what he argues for actually is an increase of at least three times the in price of energy and food. Well, that's a non-starter even if you accept the philosophy, it will lead to revolutions and regime changes, it cannot possibly work.

So we absolutely need to maintain the relative standard of living, while significantly cleaning up energy. A 5x drop of our carbon intensity can lead to a more or less ecologically sustainable world economy where billions can enjoy the western standard of living without fucking up the planet in less the a century.