This is a good point - FB has some smart people working there on actually valuable, tangible things (such as data centers and networks.) AI, AR and VR are large

This is a good point - FB has some smart people working there on actually valuable, tangible things (such as data centers and networks.) AI, AR and VR are largely bets on the future, but they could pay off eventually. Whether they can turn any of this into a successful business (telepresence? gaming? education? healthcare?) that isn't Facebook/Instagram/WhatsApp but has comparable scale remains to be seen, and that's probably why some investors aren't confident.