Even iTunes(!) posts "now playing" notifications by default nowadays. It's not trying to be useful, it's just a "look technology" demo. If you don't want to mess around with launchd, you have to disable these pointless interruptions for each new Mac app that you install.

It's possible to silence all your devices, but even then it still affects the people around you. It's like insecure defaults - yes, you can RTFM and fix all the things in the house, but I wish I didn't have to.