Well Rat400F is not the average family. But an all electric CAN do for the average family. The average family doesn't carry a ton of stuff to and from work. The average commute is well within the range of all electrics. And fast enough for the highways.
The video that started this thread showed the car using heavy lead/acid batteries. The race to the last track day was held up waiting for considerably lighter weight lithium batteries. So, in the beginning, he was carrying serious weight, but in the end, wasn't. The Tesla is using lithium as well, from their beginning. The racer, being a privateer, couldn't afford the lithium. I believe the racer was borrowing the lithium. I'm sure Gerhed would like some, too.