It only makes sense to compare ETF issuers to currency issuers if issuing currency is like issuing ETFs. In my other posts I assumed that to be the case. But perhaps that isn’t obvious. So the question becomes, what do ETFs and currency have in common that make one an appropriate model for the other?
The answer is that ETFs and currency are both examples of risk-free nominal assets. The language stems from philosophy where there are thought to be things and names, and the names are used to retrieve the things. So nominal assets are the names and real assets are the things that they retrieve. Just as it is unhelpful to have multiple names referring to the same thing, it is unhelpful to have too many nominal assets trying to make claim on a given pool of real assets. While interesting from an etymological point of view, it is not entirely accurate to think of nominal assets as names referring to specific things.