Have you heard of "pedestrian controlled" trucks? They're increasingly common. Here's one being used to move an airplane cargo container:

They're usually small but these days some carry 15 tons and you just grab them by a handle and start walking. Often there's a lifting function (to load cargo onto/off of tall shelves/etc).

You're not always limited to walking speed, some of them have a platform the operator can stand on to increase the speed.

I could totally see those increasing in size, to the size of a full size shipping container maybe, and having a wireless control system instead of needing to stand right next to it (which could be dangerous). It'd have sensors prevent the operator from running into anything and the control would just be a pair of joysticks. Outside of the loading dock of a building, they'd be able to drive autonomously.

The job of "driver" would be replaced by just a team of people who load / unload the cargo and plan/supervise the truck. And I don't think it's far away at all - we're already seeing it with smaller cargo loads (is 15 ton all that small?).