Yes, there is a technical reason Bigbee.
Rear hub motors cannot use the normal derailleur cassettes since their spindles are too thick, needing to incorporate cables through them.
Therefore they have to use multi sprocket freewheels which only have up to 7 sprockets and more commonly six or less, the reason being that a freewheel's bearings are inboard. Small sprockets far out mean a large twisting force on the inboard bearing bringing unreliability.
They could of course use two or three chainwheels, but designers prefer to avoid that added complication when there can already be so many controls on an e-bike's handlebars. The chainline can also be a problem, since the width of a rear motor pushes the sprockets outwards, so a two or three chainwheel set could mean mounting it wide and splaying the rider's legs.
And there's also the fact that e-bikes are generally regarded as utility bikes and not sports bikes so lower speeds are expected.
Pedalling speeds (cadence) are also an area for disagreement. You remarked on spinning like a hamster but were probably only spinning at around 60 rpm, 70 rpm at most which I would regard as comfortable. The accepted most efficient pedalling speed is in fact around 90 rpm, making hamsters look like they are asleep, so whatever gears are provided, they won't suit everyone.
However, it's also relevant that the Powacycle is one of the lowest powered e-bikes on the market, so it's worth you trying others. Powabyke make a couple of front motored models with 24 gears which would more than look after anyone's gear requirements, though I think that's OTT for an e-bike.
.