The crime rates in other places is irrelevant if the city you've lived in for the last 20 years has become noticeably more dangerous.
This is not "a narrative that keeps being pushed without merit", in fact the people who dismiss such claims are often the ones who live very insulated lives.
There are areas where people do drugs openly, and overdosing, too, and no one cares. A cop walked past a lady overdosing.
You should watch videos of YouTubers going to these areas if you do not want to do it yourself.
The areas are famous for tourists where most phone snatching is rampant, 18 a day at a minimum, on one famous street alone.
FWIW, I am talking about London.
Oh FFS.
Do you seriously consider this robust evidence?
Instead, have a look at the Crime Survey for England and Wales (HINT: This tracks peoples experience of crime and so includes unreported crime)
You are free to walk around these areas (just go to Knightsbridge) with an expensive watch to see if it is true or not. Get back to us safely to report.
Also... I literally just saw a cop walk past a lady overdosing as if all is fine, and did nothing to the woman who threw a bottle at the YouTuber. Who cares if it is on YouTube or not? I saw it regardless.
I'm guessing your solutions involve more police and anti immigration. While more social services and better prospects in life is what actually does something about the problem.