The fact that more people move from A to B than from B to A does not prove that free movement is a lie.
It doesn't make sense because it is wrong. You can buy an Audi without allowing a German to move to the UK. There is no law as to that. With the UK outside the EU and the common market it will simply become more expensive as tariffs will be raised on that. Well, at least you are allowed to buy an Audi; I don't know whether you can (no offence intended).
I think you missed the point. I can buy an Audi without a German moving here, but apparently, the EU cannot sanction the free movement of an Audi here without ALSO allowing the free movement of a German national here. But there is no logic to it. They could, if they chose to, allow it. Dogma, it seems, is the issue.
I could buy an Audi, but I won't, partly due to the VAG emissions scandal, (and the fact that the ensuing lawsuits could see VAG go under, and the warranty/aftercare with it) but also because they aren't very reliable cars, despite the hype. It was merely a hypothetical example.