I feel like binding the journal to GitHub means that it's less likely to exist over the long term (where long term means >100 years, which is as long as I would expect an academic article to be accessible for).
We produce "archive html" files where everything is bundled into a single file. We're looking into ensuring their long-term preservation with projects like LOCKSS.
Example: http://distill.pub/2016/augmented-rnns/index.archive.html