This would point to a certain conclusion indeed. But I doubt any regulating authority will let common sense get in the way of constant fear mongering: those nasty turrists are hiding behind every bush and any trolley in the aircraft and just waiting for the guards to be let down...
It is obvious that the reinforced cockpit door has been contributing to many total losses. But seeing the general climate of using some "war against terrorism" as the sole raison d´ętre for anything security related (including the whole secret service affaire at the moment), I already hear the choir shout "Many attacks have been thwarted by this doors presence". Be it true or not, it is impossible to prove the opposite, and I am afraid that no authority would be prepared to take the responsibility in case of a repeat of those hijackings of 2001.
So whether one likes it or not and leaving aside any common sense, those doors are likely here to stay and those souls that perished in the above mentioned accidents and the one in question as well are apparently just acceptable corollary damage in a greater game.