Indeed. It looks like everything either malfunctioned or was intentionally turned off all at once. A long time ago one of my servers had a very crude monitoring system, it would send me an email every half hour saying "I'm still alive!". Hard to believe that kind of simple thing can't be implemented on a 21st century airliner ( or maybe it is, then forgive my ignorance please). A simple beep beep signal saying "I'm still flying!", every minute or so, with the plane's location as a bonus.

Edit: that said, if the plane starts breaking apart at cruising altitude, it wouldn't help much with finding it...so maybe self-powered transponders in nose, tail, wings, engines etc etc, nicely sealed in "black box" style casings might help. Or maybe they have that already and I know absolutely nothing about modern planes (or planes in general).