Technology

Because in my country they are limited to 15mph by law. In the USA they are limited to 20mph, which would be 20 minutes faster, and still much longer than the average American's commute, which is 27 minutes. In the context of the original post, there will still be many people whose commutes have stretches with much higher speeds possible, for whom the difference would be even greater, so even there "almost never" is clearly wrong.

Maybe there are people advocating for electric motorbikes, rather than electrically supported push bikes, though I don't see them. But of course the faster you go on any kind of bike the more dangerous it is - riding an ordinary bike is pretty safe, and the exercise benefits mean it's overall good for public health. But encouraging more people onto motorbikes, even zero-emission ones, could easily be a public health disaster due to the inevitable increase in fatal accidents. Cars are much safer per mile travelled, which again goes to the above context.