Sure, what could possibly go wrong with a radical decision taken by a narrow majority, with a significant part of the voters that supported it having racist motivations (even if the concept of Brexit itself is not racist), others motivated by lies (millions to the NHS et al) and the vast majority of economists describing it as a shoot in the foot?

I don't think it will be "doomsday" either, but I think believing that things won't go downwards is an exercise in self-fooling.