No, as those also have ICE motors. This is more like having an EV but instead of charging the battery directly you fill it with diesel. Then there is a diesel generator that runs constantly at the most fuel efficient RPM it can. Any engine has an ideal RPM that it can run at with significant savings - thing trying to go highway speeds in first gear for the opposite idea. Instead of the generator having to absorb any power spikes, the electric motors do that and use the stored energy.

There is also a startup company in BC that I saw has been implementing this idea into long haul trucks for substantial improvements.