Answering that specific question, 98 jumped up 16% this spring and... that's it. Except for that, it's an ordinary curve compared to, say, 5 years ago. And that's mostly the result of actually bombing the refineries.
And yes, if US and EU were serious about helping Ukraine win, this would have already happened back in 2022. Or better yet, back in 2014.
As it is, US & EU sanctions seem to be more of a theater mostly for the benefit of the population of those countries, so that their politicians can sincerely say that they "support Ukraine".
Depends on the claim - some are, some aren't. The problem obviously exists, but the coverup is good enough to make lots of people think that the war happens on another planet and doesn't affect them (e.g. gasoline export ban).
The only reasonable definition of "work" is "stop the thing that motivated the sanction from happening". With that definition, sanctions rarely work (or if they do, not in a very effective way). Russia is still at war with Ukraine. Iran is still developing nuclear weapons. North Korea did develop nuclear weapons.
Let's not kid ourselves. Russia is still killing Ukrainians right now. They're still occupying Ukraine's land right now. Is this what "work" looks like in your dictionary?
> Ask a russian about the price of fuel.
Oh I see. In your dictionary a working solution is not to stop the war or get lands back, but to ensure average Russian people suffer. Never mind then.
Oil is how Russia funds their war-machine. Bombing refineries makes it harder and less sustainable to keep the war going. It's not about making civilians suffer when you literally need to pressure the enemy into stopping the war by blowing up their infrastructure.