Blockchain systems are a funny case in that they don’t really need much network traffic for consensus, but they do need a whole lot of messages. All the “traffic” in a [proof of work] blockchain system consists of messages the nodes generate internally, and then discard because they’re not ‘convincing enough’ as a proof of their leadership. But yeah, if you count all those “attempted and discarded” messages up, there’s roughly a gajillion of them.