Blinking lights are also banned in the Netherlands, which does a lot better in the statistics. Even then, the statistics are kind of useless; here bike deaths are mostly caused by old people on (electric) bikes falling over or getting into minor accidents, nothing to do with lights. The statistics are skewed in ways that cannot be compensated for easily, as on average UK cyclists are younger than Dutch cyclists and therefore less likely to die or get severely hurt in a traffic incident.

Great Britain has half the bike usage of Germany. Germany has 36 million bikers (43% of 84 million), Great Brittain about 12 million (19% of 68 million), so the stats line up more than you'd think at a first glance. The difference between Germany and Great Brittain becomes laugably obvious when you look at the statistics for how many people use bikes as a primary transport method (6% GB vs 21% DE).

That said, biking outside of large cities in Germany is kind of terrible, so I'm not at all surprised about how deadly cycling in Germany, though that may just be my spoilt Dutch take on things.

Edit: my source for these statistics: https://www.ipsos.com/sites/default/files/ct/news/documents/...