You can represent a collection of nodes like that, but human readable/machine readable flow configuration, highlighting, plus composition seems like a tall ask, and JSON is a small extension that's mostly human-readable as it is.
This is adhering to an obvious crack showing in Obsidian as it is: how do you store a graph view configuration? Right now, per vault, you get one slot unless you draw in something like Juggl, which is... well it raises serious usability concerns.