> Gold trade = good.

Look up the atrocities committed on the name of countries gaining more gold sometime then get back to us on that one.

> Blockchain = good. Single network = bad.

The CC networks have much lower fraud rates than the block chain does.

> Small forums = good. Reddit = bad. Social media giants = bad.

This forum is 100% a benevolent dictatorship and it works really well.

> A local sheriff = good. An army = bad.

Plenty of very corrupt local sheriffs. Horribly corrupt for that matter.

> On device AI = good. Open source AI and datasets = good. OpenAI and closed datasets = bad.

Agreed!

> This forum is 100% a benevolent dictatorship and it works really well.

Part of the reason why it does is because there are so many other places to go to. But that is exactly the decentralized model in practice - it's not really anarchy so much so as a lot of small dictatorships, benevolent or otherwise (but you're free to vote with your feet).

"Decentralize it" isn't a bad instinct in many contexts but I am sure you are capable of conjuring a counterexample to every one of the cases you mention with a modicum of effort/imagination.