Before condemning Uber or the driver, I'd like too know exactly what went on in that vehicle. There have been some allegations lately that Uber doesn't adequately investigate its drivers. But I can also tell some stories about cab drivers and shuttle drivers too. There are bad apples in every profession and despite an employer's best efforts, one of those bad apples can still be hired. I don't know that there is a 100% foolproof way of screening applicants.
But as I said, this could have been a robbery gone bad. Or maybe the driver and passenger knew each other and this was a result of an argument. Could be plenty of possible explanations that may have nothing to do with Uber. Would rather wait for the whole story before opining.