So much work that you put into this, but yet it is so anthropocentric. The “great narrative” is written in our DNA already. We just have to admit that humans aren’t some pinnacle of Divine creation: we are standing on top of all the things we owe our lives to. The concept that “what’s good for humans is all that matters” is killing us. Our inability to find common moral motivations lies in our selfish egoism as a species. We cannot accept that we are a product of lower beings rather than magical sky puppeteers. God can’t be killed because He doesn’t exist. A useful tool for getting the town meeting started, but otherwise just a brand to be fought over by people wearing giant cheeses on their heads.
Native Americans acknowledged the gods and ancestors living in all things, and taught that we owed them our lives. Modern consumerism teaches that infinite desires create infinite resources through demanding them.
People don’t believe they are useful to their own place. That’s why they are lost. They have no control with their own hands of where their next meal comes from, and they have been separated from the ability to get it (city walls). Cities are built to service the desires of imaginary beings, rather than supporting the real world supplying them and taking their waste products. Is it any wonder that the humans living in them don’t feel they have a solid purpose that can be explained to their grandchildren?