Ok. Since you asked in what seems to be a reasonably courteous way, NI … here are a couple of thoughts. First I was stretched at the time of the referendum trying to weigh the likely economic kickback for the UK against my own preference for decentralised government and nation state sovereignty… seeing this as more democratic. Despite all the assumptions of the previous poster I actually voted, albeit hesitantly, to remain. Once the result was announced I recognised that I was actually relieved at the outcome and have continued to be positive about the vote to leave. From this you might see that I won’t defend my view on the basis of economic benefit. What I would observe, though, is threefold.
1. The present economic ills affecting the UK are not all down to Brexit.
2. The discussion above should also take account of the state of many countries in the EU both economically, socially and politically .. as well as the whole EU project itself.
3. It’s very early days to make a genuine assessment. Let’s have another look in ten or thirty years before we draw confident conclusions.
That’s a thumbnail sketch of my thinking.