The article does say that they didn't examine body injuries, so it may still turn out that Neanderthals were "more" violent, but I don't see that it matters. Humans are plenty violent enough.
I agree with the gist of what you say, if I read you correctly, Angela and that there is enough of violence going around.
As per whether it matters to know what propensity Neanderthals were also violent, I would disagree. Until recently it was assumed that Neanderthals were the more "brutes" etc. based on what? Not much, I would say. Just mainly in my opinion probably coming from a simple formula of "less evidence of what we call advancement = more violent" - a questionable presumption to say the least.
Mainly though, the reason it is important to keep studying is the all-too human propensity for seeing the alien-to-us other as less-than, worse-than, stupider, more savage, etc. etc. which seems to align exactly with the more repulsive social violence chimp behaviour, we would do well to get out of our system. Neanderthals in a way are the last other, since we've explored pretty much every existing human civilization and also largely interbred around the world.
I know lots of social science studies say that witnessing violence, whether in person or through things like movies, doesn't influence people to be violent, but I've always been a little skeptical about that. Given the present present replication crisis in the social sciences, I'd really like to see it re-examined.
One of the reasons I'm skeptical about it is that I grew up on stories of the German occupation of Italy and my father's war stories, and they reinforce many of the things I've read, which is that people do become "used" to violence, hardened to it, if you will. Killing your first animal, or person, for that matter, is a lot harder than killing your hundredth. I remember the first (and last) time my brother went hunting with my father and uncles. He said he couldn't even look at the deer. I'm sure I would have been the same, but as my father said, if eating depended on it, you'd do it. Just as if your survival depended on it, you'd kill a man as well.
I think there are some people who are easily impressionable (I believe this is an inborn trait) and thus would fit the studies that are in the minority saying violence exposure begets violent behaviour. It is worth to note, here though many of these studies are pretty vague and coming from an ideological position, the latter of which is not conducive to finding the truth. I agree this area does warrant more rigorous examination.
As for some people becoming used to violence, such as war experience for example, this is a complex matter, as I think you would agree. We would have to define what it means to "become used to". It can mean tuning out and establishing a protective shell. It can mean turning a blind eye to atrocities because of a sense of powerlessness or life threat to one's self and family. It can mean crossing over to the "bad side" and turning on your neighbour who was once your friend at least not someone you would consider hurting. To me, the latter is really the only true example of seeing violence and then becoming violent among non-military.
As per the first kill being hard and the rest not so much, which speaks to a belief in violence as an easy corruptor, leading us to become callous, indifferent to the suffering of other creatures, and last but not least, a kind of fatalist foregone conclusion that we can't help but become bloodthirsty, I would say no. This is not a foregone conclusion. Some people do go down that road. I believe those who do always had this in them, but merely had it curtailed by laws and the need to get along. Yet, others do not become violent, but lose their marbles or just check out from society (ie. PTSD, used to be called shell shock).
I contend that it was much better in the days when there was a strict military/social class and mercenary units, rather than in late modern times when we have conscription of the mass of male population. I will explain why I say this. I believe we will never get rid of war, as it is in our make-up to war and in this sense, those who have been exposed to violence are at an advantage and it can argued, have a more realistic view about our nature and thus a better chance of staying sane. But also, there are people who do not flinch at violence or killing and this is in-born as well, as has been supported by recent psych studies.
I have never been hunting, never butchered an animal. I haven't even caught a fish! I had a hard time when my dog killed a chipmunk. I would say this lack of exposure to my roots of survival, doesn't do me any favours. I would be able to kill if I had to for survival and I would kill without remorse if my kids' life was threatened.
Over and beyond that, people can commit horrific acts of violence on other people, even defenceless people, out of extreme emotion, drugs or alcohol, or just generally a lack of human empathy. Of course, the capacity for that varies.
Personally, I've always felt that the notion of original sin, or of an id which must be controlled much better explains the reality of human nature than all the romantic notions born from most philosophical musings.
If anyone hasn't read it, I suggest "Lord of the Flies".
I'm in agreement about original sin. To me it is the perfect metaphor for how once humans developed consciousness, we also developed the dark side of this and that is to come up with more and more creative ways to be jerks. You see this in other animals as well. The more intelligent ones can manipulate and torment.