@Martin Rundkvist A US dollar is way more real than a DogeCoin or an NFT monkey picture, because it's an official "I owe you" from the United States government, no matter what your opinion about it is.

I'm not sure what you're talking about concerning "the manipulation of coins with an actual value in precious metals". Most coins, even made out of precious metals, have been worth more than their weight in the corresponding metal for a couple of important reasons: you'd rather have people use the coins as currency rather than melt them for a profit, and it's cheaper to make.