Not everyone uses bitcoin for illegal reasons though but that's one of the arguments against bitcoin and it's so called anonymity.
Nearly everyone's using bitcoin is a suspect, according to FATF. According to
this paper, if you use anonymous communication (Tor or VPN), or if your IP isn't whitelisted, or if you gamble, or if you try to withdraw your money off the exchange, or use more than one cryptocurrency, or just do self-custody; in all these cases, you're a red flag according to anti-money laundering fantastic nonsense.
In other words: If you use bitcoin, you're guilty until proven innocent.