Point me to a historical example of the US government saying "Use dollars or else!" and I'll change my tune. I think foreigners use dollars because dollars are actually a really great currency relative to the local alternative ... or bartering (3 goats for 1 iPhone sort of thing).
My objection to your argument is that USD is better than alternative cryptocurrencies because the Federal Reserve does a good job of managing the stability of the value of the currency, and that's a social good for everyone. If your latte costs 3 dogecoins today and 6 dogecoins tomorrow you can be like "lol. so latte. much coins." That's funny for you and that's great. But if a bushel of wheat doubles or triples in price overnight because it's priced in some weird volatile currency, people will starve. And that's not funny.
I moved to Chicago recently and I work on the technology behind some of the commodities markets here. I guess that has sort of forced me to think more about these kinds of things. If you are in Chicago hit me up and we can bullshit face to face (over coffee that's probably better than whatever you have in SF. Zing!)