A format cannot be both human and machine readable. JSON is human readable, that's the point of it. Human readability is great for debugging only but it has an overhead because it's not machine friendly. Protobuf messages are both smaller and quicker to decode. If you're in an environment where you're handling millions of messages per second binary formats pay dividends. The number of messages viewed by a human is miniscule so there's no real gain to having that slow path. Just write a message dump tool.