Earlier quoted context omitted.
Anecdote is not data. It is both true that the police absolutely suck at handling petty crime, and the Met have a fairly terrible reputation; and that more serious violent crime is much, much less of a problem in London than it used to be (and less than US cities, of course).
Sure; but the article's premise is that street crime is falling (and as a result, the police, which, presumably, has more free time on their hands, can focus on other things). Assuming petty crime is street crime, and seeing that you agree that the police suck at it, is the article's premise correct?
Not sure about the UK, at least in Canada it's poverty/people being broke. More homeless people and the general harassment they inflict on people in their surrounding area, more petty crime that the police don't bother investigating so people don't bother reporting it. More theft from grocery stores, more petty scams for <$1000 &c.