The magic of our progenitors may be dangerous, but it is only as dangerous as the Sun above. Its discrimination is unjust; while a mare that may call the weight of the heavens themselves down upon those who have lost Her favor sits at the top of our world, there will always be a present danger. There is nothing more to fear from the manipulation of the body or soul than there is from She whom we hail as Goddess.
Dark magic does not corrupt, it only enlightens. As one learns of how life came to be, one will naturally grow jaded. Some lose their minds, or grow intoxicated of the power the arts grant. For the disturbing nature of some acts we make possible, it certainly seems to correlate with those raving lunatics that raise armies of the dead or see fit to bewitch a spurned love out of snubbed jealousy.
But there is no inherent fault within our arts that steals sense and compels evil. Those who are unable to handle the impossible responsibility we are all saddled with only carry the fault of ill temperament; they themselves should be singularly blamed for their crimes, not the tools they bring to bear, for those tools are well and truly benign. It is only magic, and as the lost Pillars of Equestria oft spoke, magic is the wheel by which our world turns.
If we are to be measured, then let us not be measured at our worst. Our greatest are paragons of stoicism; they who stand at the gates to Hell do so without care for their own safety, but know that there are many things that must be safeguarded. They do so without expectation of a reward; rather, they have grown to accept that they are hated. They do not care, nor did they care as the sun bore down on them with all Her fury.
For they fought so that the sun may rise in the morning.