Ecotech - unfortunately not my invention, but a word coined by John Micheal Greer - is but a step on a long road back to the digging stick you mentioned. As resources underpinning our high tech world slowly but surely run out, and as recycling becomes less and less an option (lacking the energy to perform it, and eventually things to recycle), we will found ourselves on a long slippery slope down the technology hill. We will have to give up technologies one by one in the coming centuries, until (perhaps in a thousand years from now) we end up using truly renewable materials only (wood, bone, natural fibers etc.) and return to a neolithic farmer craftsmen society, with some stone monuments and perhaps cities here and there. This modern society we have today would be just as unimaginable and unbelievable to our descendents far in the future as Atlantis is for us today.