Mr. Holmes was prescient beyond his understanding. The "technological change and material growth" Ram Dass describes are a direct result of cheap energy. As the age of fossil fuels draws to a close, it will require a return to a simplicity few can comprehend. (And no, alternative energy sources will not replace oil.)

Put another way by some famous scientist/philosopher dude:

"Any intelligent fool can make things bigger and more complex... It takes a touch of genius - and a lot of courage to move in the opposite direction."