Unless there is someone here who can shed more light all I can see is from way the EU members treated Greece it made it very clear the EU was never going to let the U.K. leave and profit from the deal.
I find this unfortunately phrased. There is not much the EU can do and the EU has no intention of "punishing" the UK.
But the EU will
1. Protect its common market and the four freedoms
2. Will not give a European country the same deals as a non-European country to protect the European idea. (e.g. won't insists on freedom of movement with, let's say Japan).
Both things are hard to comprehend for many Brexiteers.
Most economists told us that the overall economic pie after Brexit would be smaller..
So the idea that anyone would benefit seems like a fantasy.