Lol at expand the rib cage.
Laugh all you want. You may be technically right, but bodybuilding is also about appearance and pullovers may make your chest appear to be larger (more expansive). It also is a great breathing exercise, which can improve lung capacity. Shoulder's down, chest out....improved posture.
Will pullovers expand your ribcage significantly?
Not necessarily, but it will train the muscles that expand and constrict the ribcage (intercostals, external intercostals, serratus anterior, SCM, scalenes, diaphragm, etc...) allowing you to
potentially increase the volume of the ribcage to tolerate greater amounts of respiration.
Load here would also likely
increase cartilage thickness and potentially the density of your ribs.The Diaphragm makes up about 45% of your breathing ability (chest expansion ability), and I see a lot of people with dysfunction here on a regular basis.
Pull-overs will also stretch the abdominals, and can alter posture; If for instance, you have a kyphotic posture, may also alter the appearance of your rib-cage, simply by creating better looking, more up-right upper body posture.
