This is true. Straight after Russia invaded, oil prices went through the roof. The EU bought a ton of gas to fill up everything they had.
The problem is that every penny they made then, they have now lost in much larger quantities. The national wealth sat at $170b at the start of the war. At the start of this year it was down to $85b. The reckoning is that the wealth fund could be depleted by the year end. I personally find this unlikely. What is very much going to happen though is that the wealth fund will be needed for any recovery once this is over. How much will be left?
Russia has over $300b held in sanctioned banks overseas. If they can retrieve any of this, then that will be a major get of jail free card. I cannot see banks just handing this over to Ukraine as compensation. That will not happen. I can see Russia been held accountable for the stolen companies and hardware that they decided to just keep and not pay off anymore. A lot of which will be those airplanes that they kept in Russia.
The amount that is now coming in from fossil fuels is less than half of what was being sold at the start of the war. There are additional costs to selling the oil now. It now has to be shipped in large quantities, when before it was piped. The pipelines to China and Turkey are at capacity. The rest is sent by sea.
Piped gas sales were killed off. There is not much in the way of facilities to create liquid gas. They also have to have facilities at the decant port where ever that is. Russia is sitting on a lot of gas it can do nothing with.
The Ruble is now 1/20 of the value it was before the war. Every import is now cost 20 times more.
Russia is also loosing approx. 3 vehicles to every vehicle destroyed in the Ukraine hardware. The war is proving to be a lot more expensive for Russia when it comes to hardware losses.
Putin has ruined the economy of Russia not just financially, which will be a long term loss, but demographically also. It is estimated that 20,000 have been killed in the fighting, with 80,000 injured. There has been a mass exodus of young men trying to avoid conscription. The population is going to be very unbalanced when all this is over. That will have additional costs.
So yes it made a bundle at the start of the war. Russia is not sitting so pretty now. The whole exercise is a shambolic waste of life.