Most drivers can't handle trailers. The roads would be so much more dangerous if trailers were commonplace.
Trailer hookups can be legitimately difficult. Even in the simplest case, they can be time-consuming.
Humans are notoriously bad at backing up with a trailer attached.
Heavy trailers (batteries) are extra dangerous -- tail-wagging can be scary!
Cars with trailers don't fit in parking spaces.
...
A replaceable battery has to be in the underpan of a car. Or split across several battery modules, but keeping the center of gravity low, and between the axles.
Trailer hookups can be legitimately difficult. Even in the simplest case, they can be time-consuming.
Humans are notoriously bad at backing up with a trailer attached.
Heavy trailers (batteries) are extra dangerous -- tail-wagging can be scary!
Cars with trailers don't fit in parking spaces.
...
A replaceable battery has to be in the underpan of a car. Or split across several battery modules, but keeping the center of gravity low, and between the axles.