The underlying cause is the illusion created by fiat. It's a trick.
People have been unknowingly getting pay cuts each year for the last 50+ years. They are unaware because they receive more currency units each year and are still able to afford the same everyday consumables.
They don't realise that the consumables have been getting cheaper and cheaper over the decades (through efficiencies of production) because currency devaluation causes prices to actually go up.
It's only when they try to buy hard assets like real estate that have retained their value and find them impossibly expensive, without understanding why.
Then you've got all the devalued pensions and savings, and other stealth wealth transfer through "capital gains" tax (the more the bankers print themselves money to lend out, the capital gains tax we have to pay) and income tax bands that don't track nominal wage increases etc.
GDP appears to increase, but it's just an illusion caused by the devaluation of the units it's measured in. In the US it has been going down for decades.
It is a slow transfer of wealth from the population to the bankers. People work harder, but find themselves increasingly struggling to survive. They become unmotivated and ultimately when the deterioration in living standards becomes too much, revolt.
And that's only within the country that's printing the money. For other countries using that currency, the effect is even worse as the entire country is stealthily looted.
All the time, the bankers are acquiring all this wealth and are becoming richer and more powerful than many people could imagine. Able to control governments and mass media alike.
This is why Satoshi Nakamoto created bitcoin.