I'm sure the Russians are as interested in these crooks as the Americans, as it would be attractive to seize their assets. They will not extradite them, but they might wish they had been.
Why? They bring in millions of dollars to the Russian economy.
Why would they shut them down when they can just recruit them? Think of these ransomware groups as the minor leagues, the best get to move up to Russia's cyberwarfare teams.
LOL. A good portion of cyber security attacks are government military operations. You think China or Russia is sad that hackers closed down our gas pipelines?