As BTC, Fiat and Gold all three have both pros and cons. which one is better for multiplication of money in present circumstances and where risk is found.
As you said, all of them have respect and value in their respective jurisdictions and if you want to know, you have to different their actions for long term and short term. And the three assets you mentioned, is is only BTC is volatile while gold and fiat are stable assets. Fiat is is not volatile currency but it is a stable currency that causes inflation in the whole world. Gold is an asset that is stable in price unlike bitcoin. And when we come to risk it is BTC 100% because it is a volatile digital currency while gold might be 10+% while Fiat zero risk. In my country nobody buy fiat so I don't know if their is any volatile in it. But there is devaluation and appreciation of the Fiat money.
In conclusion, BTC is the best to invest but don't rush to invest and make sure study it well before involving in it.