The FBI has already proven pretty well that with a big enough dragnet (and resource that places like the NSA absolutely have), they can associate people to wallet addresses. It just takes slipping up a single time and they'll find you.
The upside of crypto currencies is decentralization, but a public ledger is public to law enforcement as well. With time and serious funding they often can link wallets to people.
I’m not saying it is good, only as a matter of fact it is a thing.
The FBI has already proven pretty well that with a big enough dragnet (and resource that places like the NSA absolutely have), they can associate people to wallet addresses. It just takes slipping up a single time and they'll find you.