Earlier quoted context omitted.
Well wasnt that a good thing? After the extermination of Melos they could credibly say they were less responsible for the actions of the polis. And had a higher chance of deflecting the inevitable revenge on to the non idiotes Athenians.
If one civilization is taking revenge on another I don’t think they would show that much nuance. For one thing, wouldn’t everyone claim they were against their old polis? How would the invaders have any idea who was an idiote? I just don’t believe it’s at all easy to avoid the fate of your nation , and I especially doubt that the politically ignorant have a better chance of avoiding that fate than the well informed.
The counter extermination was only 5% of Athens total population, or so historians say, so it seems like a lot of nuance was shown.