There was a very reasonable interview on R4 Today this morning (see BBC Sounds) with Ireland's Europe minister who set things out very clearly, after we had heard a report from the chairman of Marks & Spencer rather stressing how difficult it was when they filled in one page of a long form in the wrong colour of ink. It all sounds as though Johnson's government and its cronies are intent on having another trhy at stirring up feeling against the EU because of problems arising from the protocol they wanted, they negotiated, and they signed up to accept. One can only hope the EU holds firm.
It seems like M&S will need to employ administrators that can fill forms in using the right colour of ink, rather than complaining about their administrative shortcomings.
I don't think it is quite right to be saying that the protocol was what they wanted. They wanted out of the EU Single Market and Customs Union. they did not want the Protocol, and a land border on the island of Ireland was simply not tenable in the International politics domain or for any possibility of an EU trade deal
So the protocol was the only possible way forward, for good or for bad, aside from 300 years of negotiations and the opportunity of leaving the SM & CU in their lifetime slipping away. They were not going to let the Northern Ireland question rob the rest of the UK of their destiny.
The EU thought they had the UK in a pincer movement, to try and prevent departure from the SM & CU. They extracted signature of the protocol pretty much under duress, as there was no other alternative. In these circumstances, it is unsurprising that there is disquiet of the Protocol from the UK . When one of the signatories of an agreement feels cheated or disadvantaged there is rarely any good to come out of it. The history of the UK has plenty of experience, often with the boot on the other foot!