Thanks for the great post about a very important topic!
Gold cannot be replaced. Crypto coins can be. Gold will always be worth something even in a Mad Max scenario. We have modern day examples of this too. In countries where the currencies collapsed, people would pan in rivers for small amounts of gold to buy food for their families to eat.
Gold has a couple draw backs however. You have to protect it from theft, and it is not easy to bring your wealth with you when you move from one tax farm on the planet to another. Goldmoney.com allows you to use a credit card to purchase with gold though. They hold your gold in an account, and you buy and sell using the card as you would with other regular cards.
They do the accounting in the background. That type of system can easily be expanded globally too. It also gets around the moving your gold with you problem. You just have to trust the vault that holds your gold. That's a lot better than trusting governments to maintain the value of their currencies.
A lot of people say we are no longer on a gold standard, and I strongly disagree. Governments (banks) still stockpile gold. I'll stop when they do. They are stockpiling it, so technically that means we are still on a gold standard. Those governments know that it will always be valuable, and the rest of their economic decisions are affected by their gold reserves. This is also true for individuals.
All I know is that we need an easy way to make transactions with people without an easy way for governments to devalue what we use as currency. Goldmoney isn't the only way. Perhaps there's a better way. I'm not an expert. All I know though is that crypto is the opposite of Gresham's Law, and good coins will replace bad ones. Well, we never know when a better coin will come, so that doesn't make crypto a very good store of wealth in my opinion.
In other words, it may not always be worth something as gold is.
RE: Do Currencies Need to be "Backed" by Something? The Difference between Currencies and Commodities