sidenote: what kind of organization does bloomberg.com have going on? this is under '/graphics/'?
If I had to take a wild guess, the author/editor of the article might've wanted some fancy stuff (like the header videos and scroll behavior, for instance) and it was easiest to do that on this platform.
Yup. We set up a system for publishing git repos with static html/css/js to /graphics for our interactive charts.
When the features desk for the new site started up a few months ago it was much easier for them to piggyback on our stack.
Many journalism organizations (including bloomberg and NYT) have kept the nomenclature for their special feature and 'interactives' groups who do pieces like this in non-traditional layouts with custom art and interactivity.