As I understand it the scheduled 1:1s can provide a release valve for employees who get so focused and heads down they neglect interpersonal relationships or concerns. They're meant to avoid the problem of emotions being bottled up too long then exploding. Can also help to batch concerns so there aren't constant interruptions for minor things that can be addressed later.

Obviously it's not a perfect approach as one cannot force candor or trust, and frequency must be tuned to the needs of everyone involved.