The other day someone argued with me that people should not coinjoin, since that mixes their coins up with crime money.
This is inherently wrong. Coinjoins are the only way to ensure that people you trade with don't get told about the size of your stack. Or at least the size of that particular UTXO.
Without a coinjoin an employer that pays is btc will be able to see who you pay money to.
If everyone coinjoins then they will become completely normal privacy behaviour!