The amount of currency does not have to correlate with the size of an economy. When the economy grows while the amount of currency stays the same then your money simply becomes worth more. For the overwhelming majority of history this was taken to be a good thing. The argument for inflation is that if money become worth more over time then it would discourage investment and encourage money hoarding.
That's probably not untrue, but that critique doesn't simply make the alternative better. Money becoming worth less, inflation, creates an arguably worse scenario where now wealthy individuals are motivated to hoard things instead of currency. For instance Bill Gates is currently the largest private landowner of farmland in the US. This issue is where you get the WEF also publishing their 'You will own nothing, and be happy.' goal. I find this more unpleasant, and even dystopic, than Scrooge nosediving into his stash of ever more valuable dollars.
Another major issue here is that lower classes are the most unable to deal with inflation. They can squirrel away some money, but in an inflationary system that's the last thing you want to do. For instance stuff like bank CDs are basically just exploiting economically illiterate individuals. Nobody wants money in an inflationary system, but lower classes need immediate access to their money for the next time e.g. their car breaks down, and they are extremely risk averse. The net result of this is a system that not only perpetuates but directly drives ever greater extremes of wealth inequality.
If you want to see how much a deflationary currency fails as a currency, just look at bitcoin. The wild value swings are caused by more people hoarding it than using it as a currency, which is caused by it being deflationary. Now look at monero, which is inflationary, is largely used for day to day purchases (of mostly illegal items) and has a much more stable value, which is one of the key attributes of a good currency.
The USD was metal based, in one way or another, from 1792-1971, with two brief interludes after the Civil War and Great Depression. That's a really good pedigree.
So our current inflationary system only really kicked off in 1971 and is already looking somewhat clearly unsustainable. But what makes this particularly relevant is that 1971 was also right when major breakthroughs in computing were about to unlock a huge economic leap. That helped briefly enable the infinite exponential growth that this inflationary system requires. Without that, I doubt this system would have seen its 50th birthday.
On the topic of stability, the Fed worked to calculate inflation levels from 1800 onward here. [1] You'll notice that from 1800 to 1950 prices never shifted by more than 50% relative to the initial baseline of 51. That's pretty wild if you think about it because it includes the Civil War, both world wars, Great Depression, Spanish Flu, and all of these sort of things. Then in just the relatively calm ~50 years from 1971 to to today, prices increased around 800%.
for much of that time you could not actually receive any metal from the US, notably after the great depression domestically. The entire issue is that the US economy grew far faster than the supply of gold so could not physically purchase the required amount of gold as it did not exist.
There were ~10 years after the great depression where convertibility was suspended. One decade out of nearly two centuries is not "much."
The amount of currency need not, and arguably should not, scale with the size of the economy. Everything is relative in an economy. When the amount of 'stuff' in an economy grows faster than the amount of currency, then prices decrease - your money becomes worth more - deflation. Vice versa, if the amount of currency in an economy grows faster than the amount of stuff in that economy, then prices increase - inflation.
Inflation is undesirable, but it's in a constant tug-of-war with governments and fiat currency. When governments give themselves the power to print infinite money, they end up doing exactly that, often to the point of destroying their own economy. This is precisely why the Founding Fathers chose the US currency to be coins made of precious metals. It limits the government's ability to damage the country through reckless monetary policy.
Think about how fragile everything is already seeming being glued together by massive fed involvement, quantitative easing, and ever more archaic economic ideas like zero or even negative interest rates. And we're only 50 years into this experiment which, on the scale of something like a broad monetary concept, is barely a blink, and it's starting to come apart at the seams. And this is all during extremely stable years compared to the World Wars and other such events that we overcame in the past.
That's probably not untrue, but that critique doesn't simply make the alternative better. Money becoming worth less, inflation, creates an arguably worse scenario where now wealthy individuals are motivated to hoard things instead of currency. For instance Bill Gates is currently the largest private landowner of farmland in the US. This issue is where you get the WEF also publishing their 'You will own nothing, and be happy.' goal. I find this more unpleasant, and even dystopic, than Scrooge nosediving into his stash of ever more valuable dollars.
Another major issue here is that lower classes are the most unable to deal with inflation. They can squirrel away some money, but in an inflationary system that's the last thing you want to do. For instance stuff like bank CDs are basically just exploiting economically illiterate individuals. Nobody wants money in an inflationary system, but lower classes need immediate access to their money for the next time e.g. their car breaks down, and they are extremely risk averse. The net result of this is a system that not only perpetuates but directly drives ever greater extremes of wealth inequality.