Well, what I mean is that the application of the flashes of light to actually be able to communicate anything would need to be made into like a "language" of sorts. Morse code was just a good example of how the various speeds of flashes or sounds, specific lengths of pauses, etc. is a method already established of making sense out of what would normally be considered nothing, just meaningless gibberish. It doesn't have to be Morse code, but it's just a "language" that already exists and so is easier than making a new one altogether. That way, these flashes that we have "telepathically" sent to each other could actually hold meaning and be used to communicate something. As it stands right now, the flashes that they have sent are just a proof of concept, that "telepathic" communication is possible.