Note that this article talks about Violent Crime & its reduction. One theory to add to the mix of all others (one that is somewhat touched upon in the article)

Note that this article talks about Violent Crime & its reduction. One theory to add to the mix of all others (one that is somewhat touched upon in the article) - We are moving to more digitized, less physical (things) economy. If what you think of as being "Valuable" is not physical but digitized, it is harder for violent criminals to deprive you of it. However if we consider all crime - violent (physical) & non-violent (hacking, White-collar problems, Scams frauds etc) there will be a more interesting & perhaps less dramatic result than "Plummets". Obviously Murders (& certain other baser crimes) cannot be digitized away.