Because some relatively small number of events may have a conspiratorial aspect does not mean all events do. In this case, it does appear that a bunch of separatists in Ukraine got their hands on some pretty sophisticated hardware and, obviously by accident, blew a civilian airliner out of the sky. Now, that's not as sexy an explanation as secret US operatives standing in the bushes near the separatists, or secret Russian operatives bringing the plane down in an even more elaborate scheme to make the West look bad by making themselves look bad so they can say "Those rotten Americans are trying to make us look bad."
Something like this was bound to happen when relatively poorly trained and disciplined weekend warriors get their hands on serious military hardware. The Russians have been quite keen to back the separatists with weapons, intelligence and some of their own personnel. It would be nice that if they are going to allow these separatists to use advanced AA equipment that maybe they have someone nearby who actually knows how to use such equipment, or at very least to put a bullet in the head of some daft nimrod who thinks he knows how to use the equipment.