I'm not familiar with their software, but I interpreted their wording to mean their bug can leave your system in one of two possible states: (1) Entire system

I'm not familiar with their software, but I interpreted their wording to mean their bug can leave your system in one of two possible states: (1) Entire system is crashed. (2) System is running AND protected from security threats by Falcon Sensor. And to mean that this is not a possible state: (3) System is running but isn't protected by Falcon Sensor. In other words, I interpreted it to mean that they're trying to reassure people they don't need to worry about crashes and hacks, just crashes.