This also applies to staking oligopolies. Either all the coins are owned by the oligopoly rendering them valueless or they need to ignore blocks from others. Again, it seems that staking oligopolies are "better" than mining ones.
> Whereas if every time an outsider tries to buy some coins, their name didn't quite match for KYC and they need to resubmit their documents, or someone else bought them first, or the exchange suddenly needs to freeze all transactions to investigate an issue, you can maintain the illusion of an active market for quite some time.
This assumes that the exchanges are the oligopoly and ignores that the coins that the vast majority of coins that exchanges stake are owned by someone else and can be pulled. And no, if you freeze all transactions for whatever reason you can't maintain the illusion of an active market for quite some time.
Eh, maybe. I think there's a lot of middle ground between selling freely/anonymously to anyone and not selling at all.
> They can't stop them from running their machines but they can stop them from producing any blocks that are accepted in to the chain making it unprofitable for anybody not part of the oligopoly to mine.
I think/hope that would destroy whatever coin that was, and far more quickly, because there's no way to be subtle about that one - everyone can see blocks being broadcast and ignored. Whereas if every time an outsider tries to buy some coins, their name didn't quite match for KYC and they need to resubmit their documents, or someone else bought them first, or the exchange suddenly needs to freeze all transactions to investigate an issue, you can maintain the illusion of an active market for quite some time.