Why is everyone so apocalyptic about Brexit?

Yet another senior figure in the Brexit debate has expressed the apocalyptic view of Britain's departure from the EU under the Theresa May plan. Lord King, who was in charge of the Bank of England for ten years up to 2013, has joined those who say that the May Brexit solution is a total disaster and will ruin this country. He is actually a Leaver, so presumably he wants as hard a Brexit withdrawal as possible, leaving the single market, the customs union and anything else that smells of EU bureaucracy. All fine and good but does this venerable banker really believe that he knows better than the government how to negotiate the perfect deal with the EU? For a start, there is no such thing as a perfect deal, there have to be compromises but Lord King doesn't like any of them. I recall this gentleman wasn't exactly the fount of all wisdom when he was governor of the Bank of England. In fact he was governor when the financial crash occurred in 2008. How about that for a legacy? The whole trouble with the Brexit debate is that influential people on ether side who are supposed to sway us simple folk one way or the other, have always given us the apocalyptic future we face if we don't do what he or she thinks is best for the country. Lord King is now one of these. His only contribution is to say that the Theresa May government has been totally irresponsible and has tied Britain to the EU and all it stands for for an indefinite period without having any say in what laws and/or regulations are passed, and paying $39 billion for the privilege. Well that sounds like a reasonable argument for opposing May's Brexit. But what is his alternative argument? He doesn't have one. His only battle plan is to knock Theresa May and tell anyone who is interested in the "wisdom" of an old banker that the UK is facing a future of gloom and doom and economic disaster. Well thank you Mr Banker, there is enough to be depressed about in this world. Isn't it time we all started thinking optimistically about the future and actually laid out the positives of pulling out of Europe? I never wanted to leave the EU but since that is the way we're going, let's grab what we can and make May's Brexit deal work in our favour and the country's favour. No more apocalypse please. The best news has come from a lawyer giving advice to the European Court of Justice. He says it will be perfectly ok, legally, for the whole Brexit thing to be scrapped and for us all to go back to Square One. Hurray!!!