The globe trotting elite need to realize that ordinary people lack multi-language fluency.
The legal possibility that a Brit can get a job in Germany is not a practical one. German employers normally expect employees to know German very well.
Everyday English doesn’t have the complex rules of everyday German. A German sentence isn’t just spoken, a German sentence is engineered and uttered.
One the other hand, Germans commonly know how to speak basic English. English employers are generally far less demanding with respect to language usage - they know from decades of experience that foreign-born employees can improve their English while on the job.
The result of the language problem is that the “free movement of people” is to an ordinary Brit a one-way tunnel to unemployment and higher housing costs.
Europeans treasure their languages. Therefore, Europe can never be like the English-centric United States, at least in the 21st Century.
Your point about German vs English language skills may be right - but nonetheless Germany has the highest rate within the EU of immigration from other EU countries - higher than the UK.