I don't think you can call it a war. If state banks of all countries produce their won currencies then I will be a huge revolution in the crypto market as you know in most countries this is not legit. So, if all countries make their own crypto then it will be solved. On the basis of your second point, yes, all will prefer their own only as the currencies are used to exchange except crypto as the value of the GBP is more than USD. So, I don't think this is a problem.