The EU isn't a nationality,European is an ethnicity were still that as were leaving the EU not Europe the continent were still in that unless the found a way to move the country 😁
To become a EU citizen they would have to make a EU citizenship which we dont have,it would take a long time to set up,but to cut a long story short if they could or did yes I'd accept it,as I feel we should be part of our continent and ethnicity not alienating our EU neighbours even more than we allready do,plus I dont want too go back too the old holiday visa system its easier to travel without it.
European is not an ethnicity, it is a resident of one of a number of countries on and around the continent of Europe and those countries contain different ethnicities. Most obvious example being Spain with caucasians, Moors, Jews and Basques. Possibly more.
But you still can't have dual nationality with the EU as the EU is not a nation. Yet.