I enjoy posts like this for a thought experiment and to discuss the what ifs'. I think bitcoin will likely loose more dominance in the crypto-currency market cap because we humans like plurality and multiple choices and we will likely never accept a one world currency. Which, is also why I think fiat and crypto will coexist for sometime. Additionally, traders like myself seek to make more profits from less known crypto-coins as they become more popular. In the end, I think each coin that survives the very long run will find its niche or dominance in some area of the world or marketplace and the people in those areas or markets will decide what those coins will be. It has definitely been exciting to watch and it will continue to be exciting.