The big idea is tracing the roots of language to ancestors.
It's historical, comparative linguistics. At least for me, this is just an intensive hobby.
There's an intersection with CS in computational methods, which, is IMHO severly lacking, or better to say, rather promissing, because semantics was intractable, so far. There's a lot of exiting development in NLP, of course. Categorical Semantics gives it an algeabric underpinning ... so the whole thing ties back in with the featured article.
Most of the computational methods stuff I see in historical linguistics is about trying to put a computational gloss over lexicostatistics, which I don't think is a very promising field. Preliminary surveys of probable family groupings are one thing, but unless sound correspondence identification can be automated, I don't think the later stages of classification can be aided much by computational methods. You still want regular phonological and morphological correspondences and, ideally, shared irregularities (good/better ~ gut/besser, that sort of thing), and I'm not sure what computational methods could do for that.
But there's really a lot to do in the preliminary stage, although it isn't always obvious. I'm still seeing classifications of Papuan languages that go entirely by their pronouns, the historical map of Africa is being redrawn (to clear out the overly enthusiastically lumping Greenberg classifications), and there are probably a few more chunks to be torn off Sino-Tibetan, which could... maybe be identified by throwing computers at word lists?
It's too bad language family proposals don't come with epistemic status markers.
