I think, though, that the Economist gets the explanation partly wrong. In particular, the emphasis on the Bologna process is, well, bologna. It is important, but not for this, and it comes along too late.
I would argue instead that, first of all, the explanation differs by location within Europe. The UK has always been plugged into the world of academic economics in North America, as have, so a somewhat lesser extent, the Netherlands and the Nordic countries, particularly Sweden. Those countries have experienced gradually increasing integration due to decreased travel costs and (with the obvious exception of the UK) ever-increasing skill in English.
The big changes have been in the countries without strong traditions in neoclassical economics, such as Germany, which is still putting down the last bits of institutionalist resistance, France, Spain, Portugal and Italy. In the last 30 years, neoclassical economics has advanced rapidly in those countries. Neoclassical economics proceeds in English, so if you want to play the game, you learn the language, just like 100 years ago if you wanted to do chemistry, you learned German.
Hat tip: Herr President Direktor Prof. Dr. Klaus Zimmerman