There are different types of Coinjoin implementations, each with their own take on the same basic idea
problem 1
There have been a couple of instances that exchanges has flagged users that have been tracked to or from a Coinjoin service
problem 2
are these even fixable? if so, how?
Problem 2: Centralized exchanges are a privacy hellhole so no, I don't believe that is fixable. Political lobbying in favor of financial privacy could help a bit but I don't think that's going to help much tbh. Ultimately, centralized exchanges that store KYC information should be avoided and we should increase the use of P2P transactions instead.
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