In other words, the NSA found a better way of snooping. If they are asking to drop phone surveillance, then they found a superior method of data collection.
This sounds more like a public relations move instead of a technically inspired one.
https://www.theatlantic.com/magazine/archive/2016/11/even-bu...
https://now.northropgrumman.com/mems-and-smart-dust-the-big-...