He means a safe wage job pays a third less in the UK than Germany.
Not sure if it's true so let's look at some stats:
Germany median for software engineer: €66,000
United kingdom median: €58,000
Note depending on source, these numbers both vary broadly within the same range, but with Germany salaries being about 10-15% higher on most sources, so nowhere near the figure claimed.
You said that UK's salaries are 2/3 of the Germany ones, but this doesn't mean that the Germany ones are 1/3 more, they are 1/2 (or 50%) more. That's pretty far from 10-15%.
10-15% in the opposite direction. That is I stated they earn 10-15% more.
33% less equates to them earning roughly 50% more. The difference between 10-15% and 50% is huge!
(trivial example, if someone is earning £100,000, then someone earning 33% less makes £66,666. But Someone earning £100,000 makes 50% more than someone making £66,666)
Not sure if it's true so let's look at some stats: Germany median for software engineer: €66,000 United kingdom median: €58,000
Note depending on source, these numbers both vary broadly within the same range, but with Germany salaries being about 10-15% higher on most sources, so nowhere near the figure claimed.