One sovereign political unit (the Ottoman Empire) was weakened by ethnic nationalism (alongside political decay, external pressure, etc.); ended up in war; and the Balkan region was broken into several small states. Instead of being able to make regional policy, amortize common costs, suppress local divisions under a common rule, communally defend against outside pressure/threats, etc., these new states were weak and unstable. Ultimately their conflict drew in outside powers and led to the first world war.

The suggestion in this context is that if a library is replaced by several pieces, they will adopt different conventions, duplicate effort, not interoperate as freely, etc., instead of benefiting from a unified vision and design.