They are only banning 2/3’s of it.
If they are banning 2/3 of Russian oil but the price is increasing significantly and have to be paid in Rubles....
Hypothetically using round numbers to make the math easy...if Russia sold oil at $50 and it is now sold at $200/barrel, then that means they can sell less oil and still make money and save their oil reserves.
The only way to cripple Russia is to destroy the pipelines into the EU. That should just about do it.
Then all the electric vehicles and solar vehicles can make Europe clean and an example for the entire world. They can even use solar to heat their houses in the winter and maybe even fly their jets with solar power...hahahahahaha