Because of bitcoin does not give public details of people who make transaction with it, some people do say it promote crime. People needs to understand one of the features of bitcoin is freedom that anybody can get access to it, it does not discriminate. The privacy features of bitcoin is very important to humanity, which I know one of its advantage is for safety by using cryptography that makes all transactions safe and encrypted.
Privacy in transactions of bitcoin is much important, if their was no privacy it would have cause several criminal attacks. For those who think bitcoin encourages crime because of hiding public data of users don't understand the importance of bitcoin being private. Before bitcoin started existing monetary crime have been existing. Bitcoin is not a reason for monetary crime, bitcoin is just for everyone and does not discriminate but accept everyone.
I'm still amazed to see people who say that Bitcoin is related to crime and actually it is a digital asset that was deliberately created for crime. Their baseless claim is just to make the banking product much better than Bitcoin, when in fact the banking product is no better than Bitcoin.
Now is the modern era, where people are much smarter. Their unfounded claims will be dismissed as passing wind. Because indeed people see that Bitcoin really helps them for transactions and it is true that it offers security and speed which is not offered by banks, and that will break their baseless claims.