Seems that that were was one contact. Somewhere. At some time. The app does not know where it is. It solely relies on the exchange of anonymized tokens via low energy bluetooth.
Strange that people would not give the German government their data, but happily shovel (knowingly or mostly not) all their live into the silo of evil tech conglomerates.
With the Germany government the biggest danger would be that they loose your data. It is no evil. While those corporations are. One had the motto: “Don’t be evil”. It no longer has it.