It's an anti-social company that's a horrible place to work. Everybody knows that by now.
What nobody can know for sure is why an individual takes his life, or what circumstances would have to be different.
Take Google, which in several recent lists is the best company in America to work for. Google has just shy of 60,000 employees. Given the US suicide rate of 46/100,000, if Google were largely reflective of that you'd expect 28 suicides/year among Google employees. Of course (a) not all Google employees are Americans and (b) Google employees are economically better off than most people in their societies, so you'd expect there to be a lower rate of suicide. But it's safe to assume a dozen Google employees a year take their lives.
And if you look at them as individuals, you'd inevitably suspect work stress was involved, and if you'd look you'd probably find it -- because it's a chicken-or-egg thing. Suicide is a catastrophic loss of coping ability; when you head that way you will find trouble everywhere you turn.
When something like this happens to an individual, everyone feels the need to know why -- even strangers. But that's the one thing you can never know for certain. Now if suicide rates were high for Uber, then statistically you could determine to what degree you should be certain that Uber is a killing its employees with a bad work environment (or perhaps selecting at-risk employees).
I think its inevitable and understandable that this man's family blames Uber. And it's very likely that this will be yet another PR debacle for the company. But the skeptic in me says we just can't know whether Uber has any responsibility for the result.