The fact that they didn’t doesn’t mean that they wouldn’t have. Saddam Hussein specifically was grooming his sons to take over and had given them positions in said hierarchies to do so. The only reason they didn’t was that America killed them all. Trujillo as you said did in the Dominican Republic. But was cut short because of American interference and the fact that his father was a brutal and not very well-liked man. Whose lead he followed That does not negate the fact that they were indeed intended to be hereditary. Only showing that other empires will interfere when they can.

ML are not communists. They never have been, and more importantly never will be. No matter what they call themselves. That said, it is true. They are often a bit of a different beast. At least to begin with. Militarily reserving power. There’s often a pre-existing hierarchy with lots of competing influences. Eventually though they always whittle down, consolidating power until one is left. Most of them never lasted long enough to do that though. But make no mistake with assigning xi jinping as leader for life in China. They’ve laid the groundwork for their transition to a possible future hereditary rule. It won’t be xi jinping’s family. But likely the next leader they put forward if they last that long. It’s such an ingrained thing in human nature. We may never actually ultimately escape it.