

That’s been suggested, the problem is that that requires additional infrastructure, either digging a pit for the battery to be lowered into via elevator, or raising the car in such a way they still have access to the pack.
Former is more likely but digging pits like at oil changes is not cheap either.
Mostly it’s a chicken-egg scenario: nobody will make the facilities until there are cars to use it… And the other way.
The point was that increasing voltage allows more carrying capacity with a square root of the increase in dissipation as increasing current directly.