I think the smaller concept demonstrator is very much the test case for getting back into the 19-seater and then 50-seater regional airliner market. Beyond that, aircraft weight/size-wise, it is not anticipated that electro-hybrid-ducted fan-type aircraft will have viability. So it's the smaller platforms that on paper at least look interesting. Batteries will or can be topped-up by turbine generators (a sort of APU), so the battery is not the one and only power source.
Although range is not significant, it's all about the incredible ops costs savings - in theory, when scaled up to the 50-seater class, those aircraft should be 80% cheaper to operate than current 50 seat turboprops.