Vladimir Putin and senior Russian politicians have suggested that they want to run the map and return Russia back to its former Soviet Union boarders. Though Putin denied this, the man has an infamous history with the truth. Europe/NATO now considers Russia an existential threat and a unifying threat. Would European customers appreciate financing a potential enemy with their own valuable currencies?
Ten countries represent 90% of Russian oil purchases. Eight of them are NATO countries, one of them, South Korea, is a fellow traveler who is in talks with NATO. Europe bought up about 42 percent of Russia's total oil production per year. China purchased 14 percent and 30 percent stayed in Russia. China is their biggest customer.
https://thehill.com/policy/energy-environment/597882-here-ar... Russia
A digital currency will not be a magical weapon relegating the US dollar to history. Bitcoin Transaction Per Second speed is notoriously quite anemic. "...4.6 transactions per second. Visa does around 1,700 transactions per second on average (based on a calculation derived from the official claim of over 150 million transactions per day)..." At the time of this writing the Ruble is less than a penny to the USD and only two countries outside Russia accept the Ruble. I don't see any economic benefit by supporting purchasing oil from a potential enemy.
https://towardsdatascience.com/the-blockchain-scalability-pr...