There are a lot of ways to interpret this question, it really depends on the information and the people.
Between experts trained in the method of communication? Between experts and a general audience? One expert and one non-expert? Is it technical data? Nuanced opinion? Simple message?
This is too broad. It's like asking "what's the best wrench to tighten nuts and bolts?" For some applications that's a torque wrench, some it's a box end, some it's a socket wrench, some it's a crescent wrench, sometimes it's a pair of vice grips and a hammer. Anything that could properly be called a mode of communication has use cases where it's clearer than others.
The OBD code that's unintelligible to the lay person is the clearest way to communicate a discrete engine problem to a mechanic. A graph that plots a particular change over time might perfectly communicate the raw data, while being incapable of communicating narrative context. A meme image or referential quote might perfectly communicate a specific emotional concept to a broad group that gets the reference, while being totally opaque to those who don't.
I follow ya, I have trouble writing these questions to thread the needle between too broad and too narrow. Too broad and understandably, I get responses correctly calling it out as you have, yet too narrow and it doesn't produce the conversation and different responses I'm interested in seeing.
I suggest breaking it down into sub questions based on expertise of the audience and nature of the information: technical, narrative, cultural, emotional, etc.