e.g. Explainers on the budget process and what happened before with regulations of some kind. etc. And that only becomes relevant to readers when it becomes important and if they're interested in it.
Unfortunately because of social media, AMP, and etc. they had to fit in the article format even though they had big plans for doing richer UIs on the website itself. They basically were forced to pivot into a blog which I think they still do a good job at today cause the mission is still similar, but the mechanics of getting people to read things which aren't articles is difficult.
[This is all from memory of an episode of Erza Klein's Vox Podcast where the founders talk about the original ideas of Vox and why they ended up where they were]