Except they are different. Gresham's Law--bad money chases out good. We do have a problem with fiat and who controls the issuance, no argument there. However, "money" or "currency" is also based on history. The dollar has a reasonably good history up until 1971 when Nixon took it off the partial gold standard, the value plummeted.

Consider this: Would divers risk their lives to recover paper money from a sunken 1930s era shipwreck? Yet for gold or silver, they will readily do that. I'm not gold bug, but I can understand why--gold and silver have a loooong history as stores of wealth. That's probably more important than any other consideration--how long has the "money" been "money?"