According the the article, the espresso was rated equal to traditionally brewed. Ultrasound brewed filter coffee was rated as better than traditional.

Though it sounds like they were all cooled down since the ultrasonic brewing didn't best the water. So that is also a factor. If you like hot coffee, this wouldn't be a worthwhile brewing method.

I mean, considering how many people in the world drink coffee, it could add up if this kind of method was widely implemented

Maybe it also equalized the spread of fines. Someone get The Hoffman on the horn, we have a mission.