> If modular batteries would work, we'd have them.

We have them. Nissan is one of the ones I know that can replace individual battery modules if any of them have faulty cells. That's completely different than a battery swap for charging purposes.

Batteries are heavy but they aren't ridiculously so in the grand scheme of things. Normal, not oversized trucks, with decent range are possible without structural batteries, and that describes a lot of (non Tesla) EVs.