Maybe it's low because we don't have so many criminals with access to guns?
That said, I support self defence where legal. However it's alright as a last defence but even in your jurisdiction can be dodgy as a 1st choice. Take Kyle Rittenhouse for example or Harold Fish.
Both used guns in self defence, (the 1st one allegedly) and both sat in jail, the 1st because as I understand it they are some arguments to say it wasn't self defence, and the latter because his 10mm handgun was deemed too powerful (wtf!).
As for "Islamic Invaders", over here we call them extremists, yes the UK is a soft touch for letting former enemies have asylum eg the Taliban, and some carry out terror acts.
However, you're wrong when you say our Police don't carry guns. The ordinary Policeman doesn't carry guns but we have "Area Cars" where armed Police are roaming the streets constantly day and night and can be rapidly deployed to any incident. We also have undercover armed Police stalking terrorists or people suspect of being terrorists see video below.
Our Armed Police are trained like your SWAT, not ordinary officers. They are firearms specialists and equipped not only with handguns but MP5 sub machine guns. Do you have trained SWAT teams constantly driving around your streets for a fast response? I think not. So the UK isn't quite the pushover you may think.
Video of Lee Rigby Police reponses here and if you think our Police are pushovers think again, they can be seen here pumping shots into the suspects on the ground multiple times because they suspect they had suicide vests. Miraculously, both survived:
Undercover Police shoot terrorist dead here (actual shooting not covered but shows armed police arriving on scene and armed undercover officers who did the shooting):
There is an uncensored version of both videos from ground level but they're age restricted by Youtube.
...and UK Police in action aginst a man carrying a knife in a supermarket (no shots fired):
So to say we have no armed Police or they're a pushover isn't correct.
I agree some busy bodies (karens) will report anything. But do you shoot everyone and report nothing in the USA?
Obviously not from the OP's video. I'd say 99% of your citizens report crime rather than shoot 1st and probably thank god for it considering it would probably put inccoent people in the firing line on many occassions and based on Rittenhouse and Fish may get many of your citizens arrested and imprisoned even if in some cases they may get released later.