The main strength of JSON is that it directly maps to simple data structures that are first class citizens in many programming languages like Ruby, Python, Java

The main strength of JSON is that it directly maps to simple data structures that are first class citizens in many programming languages like Ruby, Python, JavaScript, Golang, etc. XML is a bit more complicated, and often need dedicated libraries to manage. Every time I try to get the nth text element of node X with elementtree, it's bit of a hassle.