I'll start with last first, since it seems we already covered first points.
Yes, years ago, in the 90s. I don't imagine it's hugely different. Belfast is a small city full of good hearted (not necessarily law abiding) people. I had fun with good people when I was there, who showed me round at least the ' catholic' bits of it. I'm not sure your points on that. My conclusions about travel from the small amount I have done were this; we don't need to do it if we have the imagination to do it from a book and the humility to realise that we all want the same things, and feel the same emotions. Too much is made of the enlightened world traveller, but I see that person (these days) as a little ignorant; a person who needs to be slapped in the face to understand the pain it might cause.
We have our minds, and the world doesn't need our 1st world expeditions, and we don't need to take them to understand it.
As for shreds of evidence to suggest that things would get better after brexit. There is none, and *noone* is saying there is. Nor is there any that it will get worse (unless your business depends on the eu- mine doesn't. Most of my tools are old British made, with no replacement. The rest are made in se Asia, and that's where parts come from too. I guess there are always knock on effects business wise, but business has a way of making such stuff work. I think it's inconvenience that is scaring the middle and upper classes. But so far as inconvenience goes, try this; a lot of us can't afford any of the conveniences of eu membership anyway, no travel, no food, no business or purchasing. There are things you can't know, because you don't live in that realm . This is more true with the rich/poor divide than it is between one country and the next. ) but there is enough to suggest it will get different.
Different is a ray of light, same is the same darkness. Eu or not, tories and labour will continue to screw the poorest. The U.K. Has ignored Brussels on anything that wasn't convenient to the wealthy in the uk, or govt initiatives like austerity. And yet, they were very good at helping screw the Greeks. Anyone who believes the eu are a force for good are a little deluded. Anyone who believes the eu have made the uk worse off are a little deluded. It is simply big business doing business with other big business, sometimes that lives up in favour of the poor and working classes, mostly it doesn't.
Freedom of movement is something I believe in, but the uk govt doesn't right now and they won't after brexit either. Look at all the hate mongering on polish immigrants between govt and msm. And it's still only free movement for eu citizens.
I don't think I'll convince you of anything.. I've made the same points to counter the strawman argument about people thinking brexit will fix stuff a few times but you keep coming back to it.