Unless you need to haul the block up or down an mountain or off road, I don't see any reason why an ebike with regenerative braking and purpose built trailer with low rolling resistance tires couldn't handle that particular task with relative ease. What's the max grade you need to haul you?
I live on a pretty steep hill (not exactly sure of the grade but I can see if I can figure it out with some topo maps), and there are quite a few pretty steep hills between me and the nearest home improvement store. And then about an eighth mile of gravel driveway ("road mix") or so to where I'm using them.
It's a 30 mile round trip up into where I buy such things, which is well beyond the range of my current ebikes, even with no cargo. I'd need a huge (expensive) battery to make that run loaded - probably 5+kWh, which is entirely overkill for most of my riding (I plan to build a 1-2kWh battery for long range work, but even that wouldn't haul over half a ton).
Building a trailer for this particular use case would cost me a whole lot more than just using the truck when I need to haul heavy or large things.
Is it technically possible? Possibly. Would that be an insane amount of money for infrequent use, and still not be capable of other things I use my truck for, like towing? Certainly.