Kerala is a medium-sized state, and its government is led by the Communists, who are nationally in opposition. So this was achieved with very limited resources. But now other states can copy this. Tamil Nadu and Karnataka are larger and richer states (still ruled by opposition parties), and currently have subsidised food programmes beyond the national ration system. TN is experimenting with other subsidies and schemes, and is important enough that the national government cannot ignore it.

More on this: https://www.brookings.edu/articles/how-kerala-eliminated-extreme-poverty/

Kerala recently announced the completion of this plan which raised 64,000 households out of extreme poverty, which included allotments of free medical care, food, and permanent housing