They can make it harder and slow it down and that is having effects. Russia energy sector is contracting this year, no matter what anyone says to the contrary.===
No it is not. Simply selling to western countries switched to the middlemen. And also Russia began to sell a lot of gas and diesel instead of crude oil.
So Russia turns to process her natresouces which she had been selling to Europe. And in Europe the plants who before processed Russian resource began to close.
For example BASF closes her fertilizer plants.
https://fortune.com/2022/10/25/basf-russia-gas-ukraine-europe-energy-crisis/
According to Russia, This winter the US, Germany, and the rest of Europe were supposed to freeze up and surrender. Instead it was Russian conscripts in open fields without winter uniforms and basic field gear that froze to death. So much for that plan.
Russia is having to make deep cuts in oil production as its projected revenues nose dive. Putin is going to run low on money to fund the war no matter how many left over Soviet weapons and untrained conscripts he orders into the fight.
RUSSIAN Revenue Destroyed by Oil Price Cap & Bans as Russia Loses Over $1 Billion Revenue Per Week .