You and I probably agree that a 12yo should not have the right to decide what the state should do with its might, but the argument is the same regarding how the legal voting population of this tiny state of 16k citizens decide to expand who gets to vote in their local elections.

What I say is that I’m impressed by the federal government of Switzerland for allowing even such a tiny group such self determination to select who can vote in local elections - until the UN forced them to conform in 1991 that is. I think this is why they don’t have civil wars when they disagree - they instead let others do their thing and the cantons run their competing systems simultaneously.

Regarding your question whether I would think it was ok to have a Swiss canton where local government was ran by one person, it’d be ridiculous but I would not think it’s right to use force to stop it, unless that local government hindered anyone from leaving. This is at least, as you have identified, the logical conclusion of the argument I am making, and the Swiss did until 1991. In reality no single person would likely run it well, and it would end up an economic disaster, and sooner or later change. Instead of coercion letting a hundred seeds grow, before separating the wheat from the chaff