What can those who came later, like Al-Albani, add to the science of Hadith, and is their role limited to completing what the predecessors did, such as refining weak narrations to strengthen them?

The duty of scholars concerning the Prophetic Hadith is to preserve and transmit the Sunnah to people. This duty has evolved throughout the ages. Initially, the duty involved memorization and oral and written transmission. With the emergence of fabrication and discord, the science of al-Jarh wa al-Ta'dil (discrediting and accrediting narrators) emerged to distinguish the trustworthy from others. Then, with the proliferation of narrations, the science of 'Ilal (hidden defects) appeared to distinguish the sound from the weak. As narrations expanded, the need arose to compile and categorize the Sunnah in written works.

In subsequent eras, it became the scholars' duty to understand the methodologies of their predecessors in narration and authentication, leading to the emergence of the science of Hadith terminology. Currently, Hadith scholars are responsible for publishing manuscript Hadith compilations, making the Sunnah accessible to people through methods suitable for the contemporary age, purifying the Sunnah from interpolations, clarifying disputed issues, and defending the Sunnah, while focusing on delivering the Sunnah in its entirety to people, not on inventing novelties.