I initially learned about this from a luthier and plectrum designer, Hufschmidt Guitars, a one man shop in Switzerland. Some quotes from the update he sent to his customers:

""" For a one-person workshop, the result has been pretty brutal.

[...]

The numbers simply do not work for a micro-business like mine. Even in France and Germany, I send only around 1 to 2 kg of cardboard per year. In some other EU countries, I may send less than 100 g in an entire year. Paying annual compliance costs for one or two parcels makes no economic sense.

[...]

I have therefore decided to maintain EU shipping only to: FRANCE GERMANY """