"Can you, for instance, come up with a realistic example where someone has revealed enough information about themselves to identify who they are which cannot be done without the country?"
If someone CHOOSES to reveal enough information, then that is THEIR CHOICE. That is the PRINCIPLE here. You have no right to display the flag and reveal anything that I haven't given you permission to display here. Period.
"There are reasons not to make it a choice. I am loathe to overcomplicate the software just to possibly pander to the paranoia or game playing of a handful of people or implement features that are unique to a particular community (whose concerns I believe are misplaced)."
These are your own judgements on the arguments against. You are wrong, so we disagree. I am not paranoid.
So the choice can be written into the software, you are just choosing not to do it. Give it up then and let someone else do it then. Or.. just leave it as it is until you can have the choice written into the software. I don't see your argument for showing the flag as coherent, reasoned or fair and ethical. Where are your ethics? Where are your ethics? You are not showing any with your attitude about this. As was written before, this is a classic bait and switch. Dishonest lame nonsense.