Not the above poster, but I would say the cost. Modern EVs are designed to replace cars, and so cost the same or more, while being not quite as convenient for long trips.

We could have all had lightweight, city-speed but cheap, short-range EVs for a decade or two already if that was the approach taken. The battery requirements for 60kph and maybe 100km of range are super minimal, even before you go lighter. Like an order of magnitude smaller.

Might have worked if the street infra and laws allowed it. Would have been super tough to pull off at the start, and a lot of people lack the parking for two different vehicles. I do remember some companies trying these, but there's no where appropriate to drive them.