How did they measure financial inclusion?

Hello there I need a detailed literature review of the paper below (Linked Below).
It must to include the answer from these questions:
1. What are their arguments?
2. How did they measure financial inclusion?
3.Why did they focus only on developing countries?
4.What are their methodology?
5.What are their assumptions?
6.What are their conclusion?
https://journalofeconomicstructures.springeropen.com/articles/10.1186/s40008-020-00214-4