The hurdle for unmanned airliners is not technology.
The hurdle is passenger perception.
This is true. Particularly when the engineers keep forgetting that the couple of hundred SLF in the back make the aircraft 'manned'. You want to fly an empty* airplane? That's fine with me.
*Cargo is where I can see this being accepted more readily. Amazon can drop as much junk on their way to my house as they want. I'm only paying for the one drone that makes it.