This seems like a glorified digital fiat token.
Central banks aren't interested in adopting decentralized cryptocurrencies which is what this article is trying to make it sound like, but rather, they are interested in issuing their own fiat currencies digitally, perhaps using blockchain technology.
That's very different to countries adopting bitcoin as a reserve currency, or whatnot.
To be honest, it's bound to happen given the trend of going cashless that every country seems to follow these days. Cash will be replaced eventually by something virtual that can be directly controlled by the central bank. But that has little to no affect on bitcoin. It's still fiat, it's just in a different form.