A kick scooter weighs about 5 pounds and folds up. An electric kick scooter is maybe 30 pounds, and again folds up.

A cargo bike is 60 or 80 pounds, and generally don’t collapse (yes, I know some models do).

So it’s easier to carry a scooter up stairs than it is a cargo bike.

It’s not, at least not everywhere. In my neighborhood everyone locks their cargo bikes on the street and it’s fine. That’s in the center of a bigger German city.