enlighten me

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Sellers don't set the price as much as buyers do. It starts with a producer pumping oil out of the ground. Producers must either sell what they produce, store what they produce (in limited and expensive storage) or stop producing. Stopping production has its own costs so most producers have a pre-decided floor at which they will stop producing but it's well below their cost of production - better to lose some money that stop production and have to start up again.
Many, maybe even most now since the financial markets opened up to banks and speculators, are speculators. They buy futures or options that they never intend to take delivery. In fact, they have no way to take delivery. So a speculator buys a futures contract for 1000 barrels (that's one standard contract) and the time on the contract (usually anywhere from a month to 3 years) becomes due you must either take delivery or sell the contract. But you have no way to take delivery. He's got two options: sell cheap, even pay someone who has the ability to take delivery to take ownership of the contract and, ultimately delivery on the contract, as happened in 2020 and futures sold below zero - speculators were paying those with physical capacity to take the oil.
On the other side, the producer has oil and is putting it into storage or tanks. Market is, for example, $75. A buyer needs oil but no seller is selling so he offers $76 and sellers pop up and the buyer gets his oil Now the next buyer might get $75, he might get $76, or he might need it bad and the storage tanks are nearing empty. He needs the oil desperately so he bids $77. The sellers just sold for $75 and $76 They would likely have still sold for $76 but the new buyer needs to be sure he gets what he needs in the current market. He bids $80 and the market just went up again.
Typical cost of supply these days is around $40 to $50 so all sellers are happy to sell at today's $91.00 price. In fact, they were thrilled to sell at $75.00. But when demand is so high and inventory so low, buyers set the price by making bids in the market.
I can tell you more and be more specific but that would take a lot of time. I could teach you about hedging, futures, options, and, among many other things, my personal favorite, crack spreads.
edit: I forgot to mention what happens when a trader cannot take physical delivery on a futures contract and there are no buyers to buy his contract: The contract is settled at the current price and the seller keeps the oil. But the most likely outcome is the buyer sells an offsetting contract, with the same expiration date, at the current market value. Maybe he bought his future at $75, or $75000 for his contract, and the price today is $30.00 Now he sells for $30000, losing $45000. When crude as negative $40 dollars, that guy that bought 75000 of oil futures now has to pay $40000 to whoever might buy his contract and it's a legal obligation he can't escape. He might declare bankruptcy but he'll never trade any commodity in any market afterwards.