Technology

How much does it cost to send that freight at that speed though?

Air freight is usually for overnight, so it definitely tends to be expensive. I don't see how this is going to be less expensive, with such a limited carrying capacity. Every pound will come at a premium.

As airships get bigger and bigger they'll be able to handle more cargo

OK, to improve the payload of an airplane you can improve the aerodynamics, increase the wingspan, use more powerful engines or lighten the frame/use newer fancy composite materials. The modernized A350F doubled the payload of the previous model.

This airship is a prototype and parts of it are probably overbuilt and could be more efficient. But it also has almost no cabin structure, so to carry more cargo they're going to have to add a fair amount of structure which is going to cut into the added weight capacity. And, the heavier the cargo is the heavier the frame and structure will have to be. To effectively double the payload, they'll have to more than double the size of the gas envelope, which is going to hit a practical limit pretty quickly. They might get to the capacity of 1 TEU (~10 tons) with very efficient design, but it will never match the capacity of even the older A350-900. And the bigger balloon is going to restrict the places this thing can land.

middle solution that fits between air freight and ships/road freight in both cost and speed.

With a top speed of 75 mph, this might match road transit but won't beat it.

It's a potential new multiple billion market solution. These people aren't developing the tech for no reason.

It's a hobby project for one of Google's founders, who has more money than he know what to do with.