This has always been stressed strongly by the books - bad things happen because people are unclear or deceptive. People who are upfront make better leaders (even on the Shadow's side - Demandred and Moridin have secrets, but they also make their positions on various issues quite clear).

This was stressed even further with Elaida, who stayed in power long past her due date because she was at least a known evil. People have trouble with leaders whose decisions and motivations they don't understand. That's why strongly-opinioned political figures often do comparatively well against more moderate leaders who don't have a clear set of policies (or at least, are not perceived as having a clear set of policies).