Decentralisation is the point that makes bitcoin safe. It prevents that the blockchain is altered. So exactly this point prevents abuse.
Decentralisation has nothing to do with anonimity. Anonimity is based on the fact that there is no connection between an address and its owner.

Everybody who is in the crypto business is doing so on his own free will, nobody is forced into it.
If somebody loses money here, that is the risk he was taking when he entered this world.

But to be fair, I think that regulations are needed everywhere. On the streets just as here in the crypto world.