Dollars (fiat currency), gold, and Bitcoin are three technologies developed to facilitate transactions in the economy. Three technologies of money. Other forms of “money” existed before gold, but gold (and silver) was widely used and still extremely viable today. Fiat currency was more or less second and I doubt it will go away anytime soon. The latest technology is a blockchain application called cryptocurrency. Even though there are numerous cryptocurrencies, Bitcoin is by far the leader, and acceptance is growing.
I believe there is a legitimate need for Dollars, Gold, and Bitcoin. Each has particular strengths and weaknesses.