This article fails to mention why the currency circulated so fast. It was depreciating: it was defined as gradually losing value, so hoarding didn't work, and the people with money had a strong incentive to spend it. The article makes it sound like these currencies worked because they were local. They worked because they depreciated, and it's possible to do this on a national level.
Other writings about this: A book chapter, The Currency of Cooperation: https://ascentofhumanity.com/text/chapter-7-02/
And a short piece about Brakteaten money: https://wiki.p2pfoundation.net/Brakteaten_Money