You have to remind yourself to take this kind of figure with a grain of salt, since every measurement technique has some kind of bias. The StackOverflow survey specifically targets SO users, Google Trends might overestimate languages that receive lots of queries due to less experienced programmers or poor documentation, and it is truly impossible to scan the entire web to find which CMS powers each site (especially since customized CMS installations might not have telltale signs that others do).
Part of it seems to be a play to get more governments, who often have A LOT of geo data on Github. Github is in many ways positioning itself to be a public repository of data, not just code.
Speaking of that, among all the startups that target developers, I've noticed a dearth of startups that focus on providing database backups with versioning, including functionality for functionally defining how to roll back to previous versions of a database and merging or "rebasing" of databases.
In the last year, WordPress grew from 29.9% of websites to 33.3%. Is that really losing favor? https://w3techs.com/technologies/history_overview/content_ma...