History never lies.

No fiat currency has truly preserved its purchasing power.
Currencies that have already collapsed or effectively disappeared:
Hungarian pengo, zeroed out within a year.
Weimar mark, fully liquidated within five years.
Zimbabwean dollar, vanished after twenty-nine years.
Venezuelan bolívar, nearly wiped out in fourteen years.
The American continental currency of the 18th century, lost its value in six years.
French assignats, collapsed in seven years.
Even the Roman denarius, known for "real gold and silver," ultimately experienced devaluation due to continuous alloying and dilution of metal content.
Currencies that have not yet completely exited the stage of history also have not been spared:
The British pound, since 1694, has lost about 99.5% of its purchasing power.
The US dollar, since its complete fiatization in 1971, has seen about 87% of its purchasing power evaporate.
The conclusion is not cruel, just冷静:
The problem has never been "whether it will devalue," but rather "how long it takes to devalue to the point of being不可忽视."#金价突破5500美元 $BTC