It is up to us to improve Bitcoin and get rid from fraudulent and illegal activities involving Bitcoin.
No, it is not up to us to get rid of illegal activities involving Bitcoin. Criminals do not care about us, we should not care about them. Most of the 'getting rid of criminal activity' things somehow always interfere with the personal lives of innocent people. Authorities should take care of criminals, not me.
We should not support fraudulent and illegal activities, we should not protect criminals or scammers. Bitcoin is very useful but if some criminals will use Bitcoin to purchase a weapon, where possibly people are murdered from, Bitcoin will take damage and we should not support it.
I have yet to hear the same thing about dollars or Fiat in general. But nobody seems to care as much as they care about the little illicit Bitcoin transactions being made. Dirty Fiat transactions are happening every single day. WAY more often if you ask me, but I have no proof so I rather stick to something that is very realistic. A ton of dirty transactions are done through Fiat daily and giant sums are moving through it. And the banks know it, and the governments know it, and authorities know it. They only do not care.
As somebody above my reply said. People will always look for ways to abuse the system for their own profit. It has always been like this and even if Bitcoin disappeared, crime rates would sit at the same levels. Did criminal transactions never happen before Bitcoin or what?