How exactly does a strong USD decrease the price of oil?
When the dollar is strong, it takes fewer of them to buy a barrel of oil. ITT there is a lot of talk about the production side of the equation, but the effect of the strong dollar and weaker Chinese demand have played a role too.
China is talking with Russia, Saudi Arabia and Iran about RMB denominated contracts, so that'll be fun. Currency risk will have to factored into contract prices.
This petrodollar conspiracy is baffling.
Countries don't hold dollars solely to buy oil.
The oil and gas industry is only about 4.6% to 6.5% of the global economy.
Countries hold reserve currencies to manage the exchange rate of their currency. Petrodollar conspiracists would be well served by learning about foreign exchange reserves: https://en.wikipedia.org/wiki/Foreign-exchange_reserves
And in any case, only 65% of foreign currency reserves are in the USD.
The US defense of Saudi Arabia has a requirement that Saudi sell oil in US dollars..