Depends on the target, some large ISR drones totally need big 20mm rounds but you scale the system down to machine guns and shotguns and build out integrated air defence systems with electronic actively scanning radar and sensors to detect and track the threats to kill
Apple itself was a major user of Xserve, Apples needs for cloud compute are massive and growing, and Apple could probably rent Xserve as a cloud to justify the cost and sell it to privacy focused consumers and businesses.