First of all the UK is one nation. So no, it is not acceptable to start slicing and dicing the country up by what parts of it voted to remain and what parts did not. The country as a whole voted to leave so that’s that. The matter is decided regardless of what various constituent parts voted for.
Secondly, it is the Yurps who insist on a hard border in Northern Ireland. Britain doesn’t want it. Obviously Ireland will have to work with the UK to ensure Northern Ireland is not used as a backdoor to continue flooding the UK with migrants. Given the UK is by far their largest trading partner, I’m sure the Republic of Ireland will be amenable to working with the UK on that.
As is apparent by the way the eu is sticking by its small member Ireland, a small nation like Scotland can expect more freedom in the European Union rather than the British Union, eh?
And no, the EU is Perfectly ine with a soft border in Ireland.in fact that’s the irish backstop which the leavers don’t want.
What solution do you have? Besides tossing out the DUP and letting NI remain in a customs union with the RoI?
If you want a Brexit, the simplest way is to let NI be in a customs union with the EU and let there be a customs border in the middle of the Irish sea. Very simple - like China-HK: one country two systems. It can work.