If it priced the oil in Euros or Yen or Riyals or Rupees or US Dollars it has to pay its costs. Sure it may end up with a profit its then free to invest those where it likes, there is no reason it has to buy USD assets. Many wealthy and/or exporting nations choose to buy US assets because its a large, safe and well established market, but it has nothing to do with being the most popular trading currency.
> America's basically given itself Dutch Disease, where our only viable industry is financial services.
Clearly this is not true. The largest companies in the USA are not financial.