The first time I realized something really weird was going on in the UK was when Dutch PM Mark Rutte made an effort to ask Cameron in 2013 how he wanted to change the EU. Rutte is ideologically similar to Cameron and wanted to work with him trying to move some responsibilities back to the member states. But instead he was gently rebuked.
It seems like nobody in the UK knows what to do, they just have some fantasies about returning to the British Empire, somehow. That's probably why Brexiteers never stop trying to drag the Commonwealth into this, as if trade with Australia could possibly replace the EU.
I should have been more clear. The UK could have banned Polish workers until 2011 like Germany and Austria did. It was entirely up to them and they decided to do nothing. In those 7 years of the trasitional period they could have tried to negotiate adjustments, but they made no such effort.
https://en.wikipedia.org/wiki/Freedom_of_movement_for_workers_in_the_European_Union