You could say that about any election. We don't test people to see how knowledgeable they are before allowing them to vote. The fact is they gave the people the vote so it is totally undemocratic to ignore them because they didn't give the results the elites wanted.
People knew enough. They knew that they didn't want to be sucked into a Federal state, which is where the EU is headed.Maybe if a lot more people had really understood the pros/cons of EU membership, how fragile the peace is in N.I. and more importantly, what sort of trade deal is realistic, the country would not be in the chaos it is in now.
I don't think it is the fault of the people that the EU and Irish Government decided to weaponize the Irish border for their own ends.
As for what is a realistic trade deal I would say a Canada style one is realistic. After all Canada has one.