The problem here is that the system should have some way to fight these criminals because we don't want bitcoin to be associated with drugs and sex trafficking, but the problem is, by solving these problems we should get rid of anonymity which is a pillar for the bitcoin technology, so it can't be done. And this problem might be a big obstacle in mass bitcoin adoption and regulations that are coming.
Almost every single currency or asset that exists in the world is used somewhere in a criminal or bad activity, and that doesn't really make much of a difference as those using it are the ones who are bad and not the currency or asset that is being used. People used to think Bitcoin is a currency used only in criminal activities some years ago, but did that stop Bitcoin from becoming famous or proving everyone wrong? No.
So no matter how hard a certain group of people or authorities try to convey it so that it looks bad and people stay away from it, it will become more and more popular and people will start using it more. So we don't really need to worry about that thing.
Here's the point.
I think everyone should look at the root of the problem, because to say bitcoin is a den of evil, then what about money or other valuable assets.
But on the other hand this is also not the fault of bitcoin itself because in this case bitcoin or other valuable assets are just objects here. What needs to be straightened out is how our attitude is in using it.
This happens because of greed and how everyone's mindset always does things in ways that are not justified and this will definitely happen not only for bitcoin but for others as well. Dirty human minds make it appear that bitcoin is ugly, but that doesn't mean that everything in it is also ugly, because this is only for a handful who can be represented as irresponsible "persons".