Also, "the horrors of war" isn't Gundam's only theme. In fact, Tomino himself seems more invested in the other ones: people in positions of power/authority too mired in their own hubris to stop being dipshits, which often extends to parental figures; the next generation being the hope to light the future; resiliency of the human spirit being the key; Newtypes feed into that, even. Every major cast member has had something going on with a parental figure, while Earth's struggles with proxy wars have mostly been in the background, so it seems clear to me that G-Witch is going in more from that angle.
(Also, imo, war was mostly just a convenient springboard for the plot at large, especially the existence of mobile suits themselves)