What do you mean by "dominant currency"? Do you mean "the most used currency in the world"?

IMO, BTC accepted as most used currency in the world is very unlikely to happen in the near future. You need to learn again how the legality of Bitcoin in each country around the world. Also, most people prefer to use Bitcoin as a digital asset nowadays. They know Bitcoin investment offers potential good profits because the value is growing gradually, specifically during the bullish season.

Well, I assume it is not impossible that Bitcoin can be used as a dominant currency in the future but I don't think it will happen in the near future. It should be in the next few years, may be more than 10 years in the future. When there is no ban anymore and the value tends to be more stable, at that time people may feel comfortable to use it as a dominant currency.