Saying "I didn't care that the customer told me he stole it, I'm just trying to make money" probably won't satisfy the victims of the theft when they see you have their stolen car.
Yes, but the part where this analogy is flawed is that cars are not fungible.
Neither are Bitcoins; they are UTXOs, which each have a provable origin and destination that is publicly known even to the victims once the thief spends it.
My question wasn't rhetorical, it's an actual attack that coordinators have to defend against for a coinjoin to succeed.
And the manner to decide which outputs belong to the same entity (which is what this attack is all about) is purely arbitrary. You have no means to figure out if someone's a chain analysis company which tries to de-anonymize your coinjoins or not. You can speculate, but there is no solid proof. Just as if Sam starts moving his coins across his wallets and then deposit them to Wasabi, you can't know if it's Sam with certainty, or someone else.
Moving coins across different wallets wouldn't solve Sam's privacy problem, he has to participate in a real transaction with another user in order to cause any confusion over who the coins are owned by.
The coordinator does not have the option to not censor anyone and still have the coinjoin complete.
Yes, it can. It will just not have people who don't want Stalin's coins as clients. So, it will just have people who treat the currency as fungible.[/quote]
The currency was never fungible, the coinjoin will just have people who passively support Stalin since the coordinator banned all of the participants who oppose Stalin.
Exactly. A miner cannot deny the coinjoin without 51% of the hashpower, he can only delay it.
Again, they can deny doing it themselves. The confirmation is practically inevitable, but they can sleep easy knowing they aren't liable for that one confirmation. Just as a coordinator can deny Stalin's coins, knowing that Stalin will inevitably find another coordinator who treats the currency as fungible.
If you think that's where the coinjoin liquidity will end up, then you should go ahead and run a coordinator with this policy to hasten that outcome.