Because people will riot if it is done by the Russian government. But if it is done by the other side, they'll just play victim and be secretly extremely happy about it, now controlling all information sources in the country.
How Russian people would know about this? You are underestimating efficiency of Russian propaganda machine. Russian government does not shy away from inflicting damage onto Russian people and pointing finger to the West.
What would happen with digital coins? Buying, selling bitcoins in such scenery?