It matters little in the current situation what any one person has said. In this Brexit debacle, it is what any one person or group of persons may do that should now be the apex of debate, especially among the Brexitiers.
The Good Friday Agreement very much drew on the European Union charter which guarantees of free movement in goods, services and people within the union and in that removed all restrictions betweenNorthern Ireland and the Irish Republic. With the coming of Brexit, those borders will have to be once again put in place dividing the island into two clear sectors with all the restrictions to trade and personal movement that may incur.
The above will without doubt incense those with Nationalist views throughout Ireland and in that the "troubles" may once more come about. Therefore, It is for each and every person who believes that Britain should leave the EU to ask themselves "am I prepared to see the war in Ireland recommence to have Britain withdraw from the European Union, is that a price worth paying."
In asking that question of themselves leave voters should remember that the "Civil War" that erupted in Northern Ireland in the nineteen sixties was not contained there, but spread also to the mainland taking many lives and maiming others.
There is also the fact that as the United Kingdom attempts to reshape and rebuild its economy following Brexit, who would wish to invest in a country where such underlying instability will exist.
It has been stated in this thread that there are many countries with open borders where the populations do not shoot each other. In that, Ireland has a history where divided communities have a history of murdering each other, and the underlying reasons for that situation coming about still exist