To call it a genetic "defect" is to assume that there is something wrong with it like, as you said, missing an eye or in the case of some super caramel's, a kinked spine. simply being born scaleless, I do not see as a genetic defect. this particular specimen having died young does not mean that it was due to the fact that it was born without scales. no one can know that until it is reproduced and proven to be the cause of a health issue.
if that were the case, scaleless rat snakes would have the same mortality issue which i've yet to hear of. same goes for "leatherback" bearded dragons. they're technically scaleless and there is no evidence that this is a genetic "defect" that causes them harm or early mortality.