I am thinking that intelligence/information enables better decisions for most goals that have to do with survival, power, status, resource accumulation.

It's in my eyes inevitable that either the superpower, or some adversaries ignore the risks and develop such machines to achieve some of all of the goals mentioned.

I also think that mediators are not necessary, it's just a means to the goal of maintaining power/resources/etc. If there are other cheaper more effective means, like providing virtual companions, or eliminate people, or whatever else, that would be the way to go about that.