Because they didn't. And anyone that is capable of critical thought can easily take the few numbers they provide in the article and do some simple calculations.

They claim the motors pull more than 1mw of power. So using 1 mw for 30 minutes is 500kWh. That means they paid 1 cent per kWh. (Spoiler. They dont)

And nowhere, does it say the plane weighted 25000 pounds. It says it "can exceed" 25000 pounds. But by no means does that mean that's what it weighted in this test.

The most likely scenario is that the plane was bare minimum rather than maximum. I doubt even passenger seats were installed.

This plane is a piblicity stunt and will never be a viable product (the company itself said it is not meant for commercial production)

This "jet" has a lower max speed than a Cessna 150, a service ceiling of 2,000 AGL - far less than any commercial aircraft. It weighs 25,000 pounds with no passengers or cargo, almost certainly it's max weight. They can't even fit a 2nd pilot

They do not disclose how much energy was actually used, just a vague "$5" figure and a listed max power of 1MW

It's just a marketing ploy and you fell for it

There are also flights where this could be used as fully electric right now, or very soon if they increase range a bit. If you fly from Tallinn to anywhere via Finnair, you go through Helsinki, that's like a 30 minute flight. And the reason you don't just drive to Helsinki is that you'd have to take the ferry which costs more money, takes over an hour and the Helsinki airport isn't that close to the port.

Similarly, you can fly from Tallinn to the two bigger islands here in Estonia, very short flights versus like a 3 or 4 hour bus ride involving a ferry. 30 and 40 minute flights with the current 30-40 person planes that company uses.