After reading about the protocol I came to a similar conclusion as you. Although it needs to be noted that the JSON serialization is defined as JSON.stringify as defined in ECMA-262 6th Ed. plus some more.

To me it's worse that key order must be preserved, which this standard does not specify the way I understand it.

Source: https://ssbc.github.io/scuttlebutt-protocol-guide/#message-f...