How much bullshit!
If you try to sell to China, Australia, UUSS and Colombia and Russia for example, you also need to comply with the regulations of each of those countries (and pay Tarifs in some).
To ease the collaboration between humans the European Union was created. But the European Union is not a country. Is the earth only collection of countries that agree to collaborate together to levels no other countries have in the world History.
It's success is so big, that people expects to act as an independent country, and complain when discovering Europe is indeed several countries. WTF!
It's not the first. It's not even the first in Europe: the first was the UK, Belgium and Switzerland came after. There are and have been others around the world throughout history too: the CSA, the first USA, the USSR, the UAE, and the Arab League (just to name a few).
Most systems like the EU don't work well after a certain size. I don't know if we can say whether the EU has reached the point where it's unworkable yet.