It is not just that they have to wait longer, but that their lives are uncomfortable, unhappy, joyless, empty, painful, experiences. Waiting yes, stuck in perpetual dysfunctional misery until they grow up. From a big picture perspective their lives in PMR are disappointingly unproductive, and saturated with fear, ego, anger, and vengeance -- Sounds like a Hellish existence to me. What else would you propose? Hanging them by their thumbs between lives? -- If, of course, they had thumbs -- that would certainly make them feel worse thereby making you feel better that “Justice“ (from your PMR perspective) had been dished out appropriately. But then, feeling better or worse is not the point is it? Growing up is the point and the system is already optimized to encourage that.
Graduating from PMR is not exactly like graduating from third grade. The PMR School spans many levels from preschool to the most advanced post doc work. There are billions of pre-schoolers and relatively few advanced graduate school professors/students. However when you get to the point that our PMR offers you few opportunities to learn or serve, then you focus elsewhere, in other reality frames that provide better growth potential for the whole system (that optimize your potential contribution to the larger system). You are always both a student and a teacher -- the ratio of teacher to student and the level at which you apply your teaching and learning skills changes as you grow up.
A look at the database containing PMRs actualized history thread will give you the details surrounding any event but such knowledge is not pertinent to your growth (thus, is not pertinent -- period -- serves only an ego function like entertainment) and can be yours, according to the psi uncertainty principle, only after you have earned the right to have access. A "conspiracy", yes -- the details you will have to gather on your own -- otherwise they will serve no good purpose (and most likely a negative one).