BANK DEFENSE TECHNOLOGY HAS IMPROVED. All but one of the bank robbers were caught. (The one who got away also seems to have wound up with much of the loot.) I think this may have been because they were primarily interested in having one last big score, and so they had not spent as much time planning for what happened after the crime. The fencing and the communications afterwards were careless.
Another factor in their being caught was that a lot of new technology for catching bank robbers had developed since the 1970’s and 1980’s. There were lots of security cameras guarding the vault. They disabled most of them, but missed two. There were cameras making a record of cars that drove past the bank. One of the cars they used made a number of runs and it was identified. Scotland Yard bugged their cars and made videotape of them in their favorite bars bragging about the heist. While they had used walkie-talkies during the heist, they used their own cellphones before and after the crime.
Mark Seal concludes his article by quoting the man who oversaw the investigation: “They were analog criminals operating in a digital world, and no match for digital detectives.”