It is pretty hard to build an off-grid society that is capable of producing the high technology needed to sustain it. Raw materials for windmills and solar panels don't grow on trees unfortunately.
It is possible to define starting conditions. The goal is to test theories - and many theories may assume that automation will solve many problems in the future. (If we create utopia and it needs supercomputers, well, we can then invest in figuring out what it would take to build those supercomputers.)
I was just watching a tutorial by Hugh mentioned in the article on carving windmill blades out of wood which does grow on trees. Though admittedly there are some metal bits too. https://youtu.be/QlWAihvSYxY
The blades are not the hard part. Windmills for grinding wheat have, after all, existed for quite some time. You need a lot of copper wiring and strong magnets. Especially the magnets are quite difficult to make.
