TG, I'll agree with the example you just posted, but IMO it's the dude's own fault for using such a worn out holster. you reload so you know the importance of inspecting your brass for cracks... well honestly I think the same rule applies to all your guns and gear as well. if a reloaded round blows your chamber up because the brass was flawed and the reloader overlooked it, is it the brass's fault?
that being said, I already stated that I prefer plastic for my Glock, but there's really no particular reason for that, just my preference. even though it's not what I prefer, I don't see a problem with a good quality leather holster, especially if it's the type that has a re-enforced mouth. just gotta inspect it from time to time to make sure there are no flaws or defects.