The biggest problem of all social sciences is that they measure only what can be measured or is easier to measure. Sorry for the redundancy, but they don't see what is hard to see and, therefore, think it doesn't exist.
I suspect there might be a lot of "de-dollarization" going on in realms that might not be easy to measure. To be specific: it is interesting that crypto-currencies have emerged as the currency of choice for illegal activities.
The article is talking about reserve currencies. Cryptocurrency isn’t relevant.