> oil producers are not necessarily happy to exchange oil for dollars. They do that out of necessity, for the lack of an alternative

The U.S. dollar is not the world’s sole reserve currency [1]. At 65% it’s dominant, but Euros, pounds, yen and francs are also used and freely traded. Nobody has to accept dollars. It’s just the easiest [2]. (Because we consume a lot and have deep, reliable financial markets.)

In any case, who do you think is pushing for more reserve currencies? Hint: the people who make money when people have to convert between reserve currencies.

[1] https://en.m.wikipedia.org/wiki/Reserve_currency

[2] Anecdote: friend, former treasurer for a major European airline, found it easier to buy planes from Airbus in U.S. dollars than Euros. They would sign a contract denominated in euros and settle in dollars. Even if that meant swapping euros for dollars and then back again. Why? Because everyone had loads of dollars and is this familiar and comfortable with dollar mechanisms for moving large sums. Nobody forced anyone to do it this way. It was just, strangely, easier.