How do you explain the data they proceed with, that these deaths are much less common in Europe where people also own smartphones? That's not an anecdote or someone simply refusing to acknowledge data.
Owning a smartphone and using it while driving aren't the same thing. I think work culture differences my contribute more than mere smartphone ownership.
However, where this starts to break down is highway miles. Shifting into overdrive and having no lights for miles, coupled with the always connected to work ethic might have different results.
I do think it ultimately comes down to culture and conditions on the road.
Drivers in Europe tend to be better because they have more training, and plenty to lose. Simply holding a phone will get you fined and points.