Nope, because we stand to gain more jobs than we lose because of the trade balance, we're also getting to keep our EU fees and tariffing their imports for yet more money. They also have to replace our funding. I think initially Britain might dip lower than the EU, especially if it goes to no deal and exit in March 2019, but later the UK will rise for all the aforementioned reasons, whereas the EU will not. In almost every export area, they have a trade surplus. Private companies have CEOs who are accountable to shareholders, they will not tolerate losses regardless of politics, and jobs will move and equally domestic producers can steal their domestic market share in the UK.
We will suffer a transitional upset, they will suffer a permanent loss. People say that the UK GDP will fall 2-10% or whatever. The EU GDP will fall nearly 20% the second we leave even before the actual consequences on trade kick in. That's not a projection either, it's a cast iron hard fact that will impact their borrowing and interest payments. Then exporters will feel the sting of tariffs and NTBs on £400-500bn-worth of exports, or about 4% of remaining GDP, with Germany being the worst affected. Then their fishing industry will be impacted by the loss of 80+% of the annual fish take in our waters. Then trade connections with RoI will feel the impact of having to be routed around the UK. The the affect on the debt market will strike. Despite the fact that Britain is not in the Euro, it still bankrolls that currency through subscription fees every year
Brexit could bury EU in mountain of debt
It's roughly akin to India suddenly losing Punjab, Haryana, Mahydra Pradesh and Kerala, or whatever constitutes it's richest provinces comprising near 20% of its overall GDP. It's debatable whether the economic affect would be worse on those leaving provinces or what remains.