They all can refine it, but the more technically adept refineries that specialize in processing heavy, sulfur-soured crude do not run efficiently with lighter grades.
https://www.forbes.com/sites/rrapier/2026/04/05/debunking-a-...
The same shortages seen in the 70's would have already happened this year due to the Straight of Hormuz - except China saved the whole world from shortages by cutting its own imports of oil by 50%. Their massive drawdown created a buffer in the world oil market that everyone else pulled from. This is why China's oil reserve and non-OPEC imports make them the most powerful country in the world now. They effectively exist in a separate oil system with plenty of capacity for themselves, while we remain reliant on OPEC.