That is just not true. Large scale coordination isn't that unheard of (see WWII, treaties and cooperations on various issues).
AGI might not even have magic technologies to offer and that whoever is siding with AGI has the power to subdue the rest of humanity is a bold speculation. Just like humans haven't even subdued viruses there is no reason to assume that to be true.
It doesn’t need to have magic technology, just access to critical pieces of software it hides in/merge with.
See how quite a few people reacted when Replika was nerfed. Imagine what happens when more important pieces of software are supposed to be turned off to eliminate a rouge AGI. (Pretty many who argue against AGI danger will be the first to argue against it.)
Have we even managed to eliminate all the dumb computer viruses from the world?
I don't think that aligns with history: we recently went through large shutdowns and lockdowns, we had and have people doing their daily work during war and massive destructions - shutting down things will not be too difficult if the need arises.
Wars are a terrible analogy because it implies there are multiple sides. Why wouldn't any intelligent being, AGI included, take advantage of that?
Not to mention the fact that in most wars there are spies and double agents. In the near future when GPUs become abundant, many small groups of people can harbor a copy of an AGI in their basement, where it can plan and re-spawn whenever the situation becomes accommodating.
AGIs hiding in basements are not an existential threat. Joking aside, what you describe isn't really different to the present (or past) - so it doesn't warrant much of concern in relation to AGI. People have followed ideologies and ideas into doom throughout history, it is not clear that AGI is a change there then.
That is, if that type of AGI ever exists in the first place. Maybe real AGI has different desires?
AGI might not even have magic technologies to offer and that whoever is siding with AGI has the power to subdue the rest of humanity is a bold speculation. Just like humans haven't even subdued viruses there is no reason to assume that to be true.