The EU knows what the pain points are and has done nothing to alleviate them. They deserve the backlash they are getting from the UK and East Europe, and their arrogance will cost them even more in the coming years.
Well, the major pain point of the EU has voted itself out, so the doing nothing strategy has worked there.
As for some "East Europe": for better or worse, they're part of the club. If they play by the rules, their objections must be heard. I disagree vehemently with them, but some workable compromise that nobody likes will be found, and things move on. That's politics. I don't have to like it as long as I understand the necessity.
As an Italian living in Poland, I can tell you that the Poles' approach is about 1000 times better, especially in regards to immigration, which has completely ruined Italy (although not because of the immigrants, but rather our inability to deal with anything seriously).
As for some "East Europe": for better or worse, they're part of the club. If they play by the rules, their objections must be heard. I disagree vehemently with them, but some workable compromise that nobody likes will be found, and things move on. That's politics. I don't have to like it as long as I understand the necessity.