Recently 3 suspects were arrested by Israel police for laundering money internationally through crypto. This money was stolen from France. This is a major international money-laundry.
Cryptocurrency has been used severally for such cases but that doesn’t make it an illegal means of transaction. People tend to use something legal and clean for illegal activity just to make it looks bad to the public and for their benefits gain. Don’t fall for such acts and make conclusions that the use of cryptocurrency poses threat to the society.
If they only use crypto to cleanse the money that they rob then yes it's not an example of illegal transaction. It's not that those criminals want to destroy the reputation btc by using it on their activities but the main reason they use btc is because it has a unique characteristic which can make them get away from the crime easily but sorry because authorities are just smarter than them, leading for them to be traced and caught.
As an old crypto user we already know that crypto is a legal currency but I don't know to some that are still new to it, maybe the news will make them confused and they will start to think negatively towards cryptos.