A conventional speaker creates a sphere of sound. A directional speaker like the one you linked creates a beam of sound. But an array of speakers could create a localized spot of sound by creating sound which would only add up to the target at that location. Of course there would be random fragments of parts of the sound (the unadded components) at other random places where the waves coincide, but for only one person in a room this is effectively the same as having a spot of sound with no other side effects.
I did forget to think that two ears would be like having two different people - there would be two target points where the sound would have to add up/subtract to the target.
I did forget to think that two ears would be like having two different people - there would be two target points where the sound would have to add up/subtract to the target.