Sony being in that dominant position puts them in something much closer to a monopoly of their segment of the market than Microsoft is post-acquisition. Building up studios takes a lot of time, which would translate to Sony further running away with their market position. I'm not exactly pro-acquisition; I'm just not anti-this-acquisition, especially when there are a lot of games and IPs from the past that Activision has no incentive to revive but Microsoft does. That is something about this acquisition that benefits customers and not just Microsoft.