The source of your claim it is unsustainable is that it takes more resources than they can get because of politics. Not because the resources aren't available. If you have roads, everything else can be localized. Solar, wind geothermal, water power, plus batteries can be very local. Internet via satellite. Water is actually not too hard to come by for residental use. Food can be a bit challenging in some places, but the roads can bring it in.
It is all sustainable just fine if we want it to be and stop optimizing for cost.