It's a classic example of selection pressures in action. When dogmatism becomes state policy, it starts being impossible to say anything contrary to the dogma if you want to have a career within the system. So, even when people know better, they just keep their mouth shut because they know that saying things people want to hear is the only way you advance in your career. And you just end up with an echo chamber where people repeat the same talking points to each other over and over.