The fact that the voltage is higher at the terminals of an inverter is a result of the current flow, not the cause of it. An inverter would work just fine with superconductors connecting it to the grid with no voltage rise whatsoever.
Okay, as I said, partly semantics. In actual electrical distribution, where we don't have superconductors, the inverter causes a voltage rise at its own terminals. Better?
In a non-superconductor, if the voltage isn't higher at the source than at the load, then power isn't flowing along that circuit. True?
In fact, the impedance of the grid as seen by the inverter is orders of magnitude lower than the impedance of your local loads.
I didn't refer to the impedance of the loads themselves, but rather the "impedance between [loads] and the inverter", by which I actually meant the impedance between the inverter and the parallel connections to loads. I think that in the real world (no superconductors), more impedance between the inverter and a parallel connection also logically entails that the parallel connection is physically farther away along the wire path. But if you prefer to think that that's just a coincidence given the existence of superconductors, I won't argue the point further.
To go back to your statement that "An inverter does not power loads closest to it preferentially;" I still think this is absolutely demonstrably false. Okay, it's not a matter of the inverter's 'preference'; but as a matter of physics,
an inverter does power the loads that are connected in parallel closest to it along the wire path, in succession.
I could prove this by putting a series of directional watt meters in between an inverter, a bunch of parallel connections to loads, and the utility. If the inverter is producing power, then you will see power flow from the inverter towards the utility in the meters that are nearest the inverter along the wire path. You will never see a meter showing power coming from the utility if that meter is closer to the inverter than a meter that shows power coming from the inverter. Or vice versa.
This would be true even with superconductors.
It's a massively parallel circuit.... [etc.]"Electricity follows the path of least resistance" is frequently said and always wrong.[etc.] Electricity follows all possible paths and the current through ... It's not surprising that the concept of current sources can be challenging to understand. [etc.]
Thanks for the lesson, but we're not having this discussion because these concepts are new to me.
One more thing: I wouldn't describe it as "massively parallel." For any inverter, there will only be one parallel connection in the system that is powered by both inverter and the next source out. That's very 'locally parallel', IMO.