Bitcoin is independent from the government. So if government fails, bitcoin is still good, and no need to exchange when traveling.
plus you can also carry money in your mind. By memorizing 16 words. You won't get hack if you have a decent hardware wallet.
Cash, Gold, Bitcoin only have value if people decide it has value.
So , if government fails as the monetary system is fucked, bitcoins value are valued in dollars, without dollars to base it on how much is a bit coin worth.
Its exactly the same with Gold, Gold is valued at $x per ounce, so without the dollar Gold is worth what?