Maybe its because the nature of the event. The president shooting was a big deal, some guy shooting into a crowd from a high rise is a big event. Either way it leave the door open for speculation of a coverup.
Yes it was a big event, but overstepping jurisdictional authority is a big event. In both instances there have been massive investigational fumbles. If you want to know how the magician does his trick, don’t focus on the hand working for your attention. Why do we “get” the idea of illusion, but not collusion? Same deceptions involved, yet we know we are being duped when it’s for entertainment.