I would like to learn more about fiat and why a fiat standard is doomed to fail.
How is fiat created? Why is it debt-based? How does it create inflation?
Your later questions answer your first question. Fiat currency fails and loses purchasing power because of inflation that is continuously made by governments and central banks. If you need an example, please look at the biggest fiat currency.
Terrible purchasing power of US. dollar over timeWhy was the gold standard better, and what could happen under a bitcoin standard?
Gold is better because it is inflation too but it can not be printed by governments. You have to mine gold, not get it from printing or minting.
With Bitcoin, it is inflationary too but the inflation rate is smaller with time, and after 2140, it will become deflationary. Currently after four halving times, Bitcoin inflation chart is already in a flat area.
How is the 21 millions Bitcoin cap defined and enforced?Controlled supply