Well, you probably could see this assertion coming from a mile away and you likely will be seeing more of it, from the political right, as the years go by with virtual reality becoming more accessible and mainstream. Killing within virtual reality is framed by this aeon article as potentially dangerous and in need of being "questioned, studied and controlled". Miss Angela Buckingham cites the same studies performed four years ago, which let children play mature rated games that they were under the recommended age to play and used dubious methods of actually testing aggression, as the main groundwork for her reasoning.
What this particular individual is asking for is that any video game that could have you killing anyone, be it a player character or an NPC, should be illegal if it involves virtual reality technology. Angela believes that this combination of gameplay elements will lead to increased violence and an actual desire for murder. Part of her reasoning includes that by perfectly embodying a killer it will make real world murder seem like a more tantalizing option for those that are easily influenced.
Buckingham also cites a study by Stanford Professors researching people who conformed to expectations of their avatar in virtual worlds, which they called the Proteus effect. Some of the things they observed included that when an individual had an attractive avatar, that person was more willing to be intimate with others. She correlates this with her argument because people reacted a certain way based on their avatars appearance: claiming that this could cause similar effects in virtual reality and bleed over into the real world because of how much more immersive it is.
Her article is a cautionary piece believing that we should proceed with care and restrict killing in virtual reality until it can be studied further. However, all the studies available and real-world data have yet to suggest any correlation with actual physical violence and in game killing: making the probability of virtual reality changing any of this unlikely.