The trend is towards structural battery packs which use less materials and make a car lighter and more efficient.

Further, some are already concerned about having enough materials to make enough the batteries we need, but with swappable batteries you now need those PLUS an extra 10-20% just sitting around recharging or waiting to be used.

Swappable batteries work best on fixed routes with known utilization and standardized to fit a particular vehicle type. That makes them well-suited for fleets and less suitable for finding a single size and shape that could pop into a Bolt, an EV-6. or a CyberTruck.