The reason we invented plumbing and sewers is so we could get RID of the stuff, now they want us to save it?
You can't have your own compost in most cities.
It's bad enough for food waste but composting your own human excrement is going to create more problems than it could possibly solve.
If we’re going to compost human waste, it would be far better for the city to collect the sludge and do it, rather than expect every single individual to do it.
With the city, they can burn it and turn it to ash, and then use it for city purposes, like flowers.