Freight doesn't get a say on who is piloting the aircraft, so that's where they will start with autonomous/automated flights. It does surprise me how willing some members of the public are willing to put their safety in the hands of "full self driving" cars despite such autonomous driving systems not being certified for autonomous driving.
I think we are likely to see full autonomous vehicles on the roads within the next 10 years, but they too will be carrying freight between distribution centres.