This is one of the disadvantages that bitcoin brings. It promotes ecrime and theft because of it's own nature. Bitcoin is certainly less traceable than fiat or credit card, which is what brings criminals to target people and demand ransoms through Bitcoin. They can then transfer BTC into privacy based coins, such as Monero, where tracking is basically impossible. These coins have protocols that are there specifically for ones privacy. Monero guarantees that no one can see the recipient, sender and the amount. This is done through the use of stealth addresses and ring signatures, so that nobody knows where the money comes from and where exactly the money goes. It is sad, but once the money is stolen, it is practically untraceable.