I can't imagine a quicker way to get on a government watch list than to participate in a Bitcoin mixer. How do you ensure Coinjoin isn't secrely being ran by your authoritarian government?

You can use a protocol that doesn't allow for a centralized coordinator with insight into the coin paths, like samourai whirlpool. It could potentially be logging ip's but can be accessed through vpn/tor

How do you know the tor exit nodes and/or VPN aren't being ran by your authoritarian government?

You don't, but all of this makes it harder to track.

Even if the government can track you through all of this, you can setup your private keys in a way that your family can still access your money if the government arrests you.

It's funny that this comic is from long enough ago that "Crypto" referred to "Cryptography", and yet it is still relevant :-)