> The main point of that previous post is that although economists tend to dislike monopoly and extol the virtues of competition, there is surprisingly little criticism of central banks among these same economists.

I think professional economist don't have "likes" or "dislikes". Also this statement doesn't seem correct in another way. I think economists try to understand what setting yields the most wealth. If a monopoly yields more wealth than competition, then, economists will recommend a monopoly.

For example, the metric system is similar to a monopoly. It doesn't make sense to have multiple competing systems here.

Same with a currency as it's a unit of accounting. Having multiple currencies would have higher transaction costs because people would have to convert back and forth daily for comparison and making purchases.

There's also the perspective from MMT, where money is a license to pay your taxes. So having multiple ways of paying your taxes doesn't make sense in this view either.