It's funny how crypto became branded as "decentralized" when actually it's the exact opposite. Every single transaction ever made is recorded onto a single central ledger. It's not even anonymous; pseudonymity (your wallet address) is not anonymity.
It is in fact cash that is decentralized and anonymous. If I go into a dark alley and give you a $100 bill, there is not a single soul other than you and me who knows about the transaction that took place.
Cash eventually passes through banks: Can't the read the serial numbers, and pretty easily at this point?
It's not like tracking credit card or Venmo transactions, but if you take out $500 and give it to someone who deposits it, and if they read the serial numbers, it's clear what happened.
It is in fact cash that is decentralized and anonymous. If I go into a dark alley and give you a $100 bill, there is not a single soul other than you and me who knows about the transaction that took place.