The amount of grief that your solution causes me is significant. I'm a legitimate customer who does nothing fraudulent. However, whole swaths of the internet treat me as if I have leprosy just because my IP address is in Russia.
If the Russian state refuses to stamp out crime that is causing negative externalities, then people should rightly stop dealing with people inside Russia as a logical response.
Please note that I am not criticizing any governments or culture; I merely wonder why we're OK with nationalism like this, but not racism.
I'm not appealing to nationalism? "Russia" could be a stand-in for any controlled territory.
For example many businesses that trade online in the US attempt to exclude people from the Eastern District of Texas in their terms and conditions. Why? Because the courts there are very friendly to plaintiffs in patent cases and they'd prefer not to get sued in that jurisdiction.
That district is causing a negative externality to people outside of it, so they refuse to do business with it.
I don't know exactly what causes Russia to be a fraud hot spot but Australia not to be, but the issue can only really be resolve inside Russia.