Yes, absolutely. Because there is a difference between images and reality. Not just a theoretical, ivory-tower conceptual difference. Physical difference. An enemy soldier is not 2 inches tall and shown to you flat while you sit on a comfortable couch. The report of a firearm is loud enough to blow out your eardrums. The preparative mindset that you know you might be killed at any moment with no notice is never transferred to a digital fictional character who respawns eternally.
When considering videogame violence, why is it always done with such extreme selectivity? Why pick out the fact that red pixels are used and that in reality blood sometimes appears red... but ignore the fact that fictional characters have no capacity to feel pain, no friends, no family, no hopes, no desires, no sentience, can be resurrected in a blink, and basically recreate not even one, not even the smallest, reason that violence is actually morally objectionable.
If violence in the real world worked the way it does in videogames, violence would not be morally wrong. It wouldn't be 'violence', it would be something completely novel. Yet, despite the vast gulf between the two things... somehow people get confused enough that they think pressing a plastic button to make red pixels appear on a little flat projection (the situation will not change one iota when VR gets huge, though I bet people are already preparing their arguments about how 'increased immersion' increases the nonexistent significant effects) of a character will prepare them for squeezing a steel pistol that will kick back against their hand faster than their mind can process, cracking off a shot loud enough to burst their eardrums, potentially ending the life of a human being who their mirror neurons is mapping onto their own self image. I don't see it.
Military training does not seek to desensitize recruits to killing. That has proven ineffective. It seeks to train them to kill without thinking, to kill before their conscious mind has an opportunity to intervene and give them chance to reconsider. It is only through that killing faster than the conscious mind can catch up that the rates of successful engagements increase. Unfortunately, of course, when a conscious mind would have refused to take an action, but has to process already having taken the action, a psychic rending occurs. Identity suffers a cataclysmic blow of the greatest trauma, training having made the soldier do something they would have chosen not to - yet it was themselves who did it, and they have to bear the burden and benefit of that act. This is the source of PTSD. It is a physical structural change in the brain, and it is horrific.
Kids are not doing this to themselves regularly for fun in their moms rec room.