I agree. Cargo jets are not usually clean-slate designs, they're modified airline designs. There are not enough cargo planes to justify the manhattan project necessary to build an automated one that can operate routinely in manned airspace. So (large) unmanned cargo planes won't happen until the system is about ready for automated pax jets. I just think they'll put the design in service for cargo initially, as a lead-in for pax.

Not anytime soon, just a little sooner.