As with any monarchy,the first born male, fathered by the King would inherit the rights of royalty. The Mayan civilization, however, became doomed to destruction with the practice of polygamy. Polygamy was widely practiced, as the kings and their successors had many children with multiple wives, fostering competition within families. Each of the princes wanted to gain more power than his brothers, and turned to fighting against one another to gain more territory. While there was little problem with overpopulation among the lower casts, the elite class grew rapidly. They all desired palaces and riches, and this put huge pressures on the lower casts to support them. The wars kept them isolated to small tracts of land where they had to build strong walls for protection. Isolation and pressure on the small tracts of land they could use for agriculture led them slowly to starvation. Agriculture was practiced only within those walls and the land was rapidly overused. Wars wiped out entire royal families and caused mass starvation. Refugees from such wars also caused overpopulation and social stress in other areas. This caused the rain forest to begin to disappear, and the civilization began to collapse when the lower casts could not support the royal class.
I know it may seem simplistic, but I see a similar elite royal class of bureaucrats sustained by productive workers as a goal that the socialist Democrats want for the United States. They are the ones who are using fear mongering tactics to enlist social compliance with their goals.
Mel Gibson is one more dupe in the left's effort to create an alternative reality that justifies their march on human freedom.
That does sound like yet another history lesson on what happens when a government (in this case, a monarchy) exercises complete control over the people.
Years and years ago, I visited Chichen Itza which is an ancient Mayan city in the Yucatan. Back then, there were theories that since then have been changed, as your post shows. For example, when our guide showed us the above-ground well, he said it was believed that young virgins (girls) were sacrificed to the god(s) there, but that they found only (or mostly) the remains of young boys there. So, their new theory was that the "kings" were keeping the young girls hidden for themselves, and then dressing up boys as girls and sacrificing them in front of the crowd.
Well, recently, I read a newer theory that young men were sacrificed willingly and considered it an honor.
But I think what you described makes more sense: Maintaining a reign of terror is how dictators keep the masses under their control.