The EU lost the exact same amount in that exchange and had to substitute it with inferior or more expensive goods and services from elsewhere.
So no, the UK is not in far worse shape as they can open up to the rest of the world and the EU cannot because it's built around the principles of self-isolation and trade barriers.
Why the UK hasn't done as much after Brexit is a different problem. Sadly, Johnson has turned to be useless, although not nearly as useless as May. I'd like to see a "UK Trump" take over for a while. It's very hard to do worse than the two main parties.