British pound has enjoyed a long history and was used as a currency for international trade until early 20st century. Then dollar took over.
One could argue it's because USA emerged from WW2 as a super-power.
But it would be foolish to say that only a major war or a fall of the empire will change what currency people use.
I'm not arguing for Terra as it was really a bad design. But it is odd that so many people just reject the idea of cryptocurrencies.
It's a big sandbox, big experiment with thousands of people working on the new primitives. Even if 80% projects are scam or failures, 20% might be revolutionary. The US dollar as it is today went through several iterations
It was kind of a stablecoin in the early days, pegged to the value of Spanish dollar which was more popular. There were also Continentals that failed and many colonial currencies that were outlawed IIRC.