How will those signals become known? Certainly point-of-use signals can be captured somewhat as they are now. They will signal that somebody has used something, and it if is a repetitively-used item, should be replaced.
But think about the counterparts of demand sensing in terms of sensing human and ecological needs.
Population density alone signals a constellation of human needs and possibly ecological dangers.
New births, deaths, movements of people, all become signals of human needs.
Facebook, Google and Amazon now mine peoples’ searches and statements online for signals of demand, aiming to sell you something. But those same kinds of signals could be used to forecast human needs more toward a sense of the common good." ()