They just host the site, it is their wiki product called Confluence. The same way Github hosts pages at github.io but has nothing to do with content that people host there.
If they're blogging about some tech, maybe they need to dogfood that first.. especially when it's due to performance
This is a stanford.edu project wiki page, hosted by Atlassian. Nothing more.
By the same logic, any performance improvement that Github might see from random projects hosted on Github, should be "dogfooded" in the same way.
It's not dogfooding when it's someone else's work.
Let's break this apart a bit more slowly.
They did not blog about this.
Their users did.
Atlassian, the company hosting it, did not write the post.
Their customers, the people using Atlassian's servers, did write the post.