> Credit where credit is due: the EU gets a lot of flack for being bureaucratic, hidebound, sclerotic, whatever, but the single currency has been a success and it's still expanding, 26 years after its creation.

For certain definitions of "success". The 2010s weren't such a great time:

* https://en.wikipedia.org/wiki/Euro_area_crisis

The EU isn't as integrated (e.g., labour mobility) as other currency areas, and so problems in one region are harder to fix.