Because airships are simple and cheap, and as the blog post says: if they can get cargo point-to-point across the Atlantic, they will put air freight out of business.
If they can't do that, at least they could be competitive.
Ships are simple and cheap. Airships are known to combine the drawbacks of ships (slow, weather-dependent) with the drawbacks of airplanes (needs to be light so it can fly).
That is not a winning combination for putting any kind of freight carrying out of business. The main reason people use air freight today is to get something from one continent to another in 24 hours. Airships will never do that.
