[kube-system]

Toyota’s system is good but I personally prefer series hybrids which have power delivery more like an EV.

[IcyWindows]

The video makes the argument that there is a lot of efficiency loss by converting to mechanical energy twice.

[kube-system]

In general, that is correct. But there are also efficiency losses by running the engine at higher speeds off-throttle, which is a weakness of the Toyota design. Hybrids run in many different modes of operation under a wide variety of load and speed conditions, and there are strengths and weaknesses to each.