One item that jumps out for me is the NuVinci hub, which from what I gather is less efficient than geared internal hubs, perhaps in part being CVT.

My mid drive e-bike has a standard 1x12 drivetrain and there's little evident loss. Do not have a hub-drive e-bike to compare against, but do have a belt-drive Shimano Alfine 11 commuter bike that is wonderfully smooth, silent and seemingly efficient. I'll note the Alfine hub costs several times what the NuVinci seems to go for, a Rohloff is even more that it. That's the gold standard.

Geared hubs run heavy—ease of maintenance vs. a standard drivetrain being a reward, along with the option of going belt vs. chain.

Lots of variables.