The demand for USD being too great is not because the American economy is strong, but rather because there is $12 Trillion in dollar denominated debt owed by the rest of the world. At 2% interest this is $240 Billion worth of USD that has to be paid out every year.

And now because of the world economy shutting down, those dollars aren't being fed back into the markets outside of the US, meaning that no one can generate the cash to repay their loans.

This is why cash is so high priced right now, even while the Fed is desperately trying to lower it. It's also why gold and silver are taking a beating. In order to raise cash not to default, foreign corporations and governments have no choice but to sell everything they own, including gold and silver (as well as cryptocurrencies).