Stefan, at 9:20 you misquoted by stating 0.08/100,000, which would be nearly 120 times instead of 12. Here's the line from the source:
In 1919 the homicide rate for England and Wales was 0.8 per 100,000 (Archer and Gartner 1984)
Then you showed the 1983-1986 UK/US statistic, 0.67/7.59, and said that "after 60 years of increasing gun control, UK murder rates got worse". If you plug in the correct 1919 statistic, UK murder rates improved slightly.