The map's lesson: architecture wars turn on operational physics, not headline speeds. Two mechanics keep pluggables the volume center. Serviceability: faceplate swap in minutes versus package-level rework. Fiber attach: pluggables face density and cleanliness; CPO demands precision packaging — repeatable low-loss coupling, detachability, blind-mate alignment. Research calls this "one of the least appreciated but most real bottlenecks in the CPO transition," a precision-mechanics, loss-budget, and field-service problem simultaneously. The deciding factor is what a technician can fix at 3 a.m.