Absolute bollocks, that's all I can say to this...
Brexit has had a direct negative effect on the UK economy. That is a fact. It will continue to weigh negatively on the economy for the foreseeable future - a fact.
Of course the vote wasn't about the economy, I have never claimed that it was! People didn't vote to make themselves poorer, well not intentionally anyway. But the national economy is of massive importance to any country. All it's plans for growth and spending depend upon it. It's ridiculous to try and claim otherwise.