I love how that clip has multiple shots of trucks absolutely full of boxes, while making the case for a vehicle that could fit inside the truck as it's replacement.
I think you just missed the point entirely. You don't actually have to load up as many items in a cargo bike, because it's inherent advantages in urban contexts more than makes up for its inability to load up as many items.
If I own a grocery, it's going to take a hell of a lot of bike trips to and from the warehouse to restock every day. Or I could employ an army of bikers. Or one truck.
Ok, so deliver food via truck. Choose the appropriate means of transportation for each type of last-mile delivery. The 200 gram Amazon package most certainly does not require a heavy truck to deliver.
It seems I missed the point. I had deliveries in mind where the truck is mostly empty most of the time. Restocking with a truck or cargo tram (depending on the environment) would make more sense.