They might want to shape developers on the job and bet that it's on average cheaper to do with functional-curious people rather than those that have professional experience in ML-languages.
Yeah fair, I definitely have developed pretty strong opinions on the "right" way to do things in functional languages, and those opinions likely do differ somewhat from theirs, at least in some cases.
I think if I want to work at Jane Street now, I either need to finish my PhD, or get a Masters degree from a sexy school to "cleanse" my WGU degree (despite the fact that I don't think I know much less than the average Ivy League graduate, though obviously I'm a biased audience).
One reason for recruiting from 'high end' unis is the kind of social networks those graduates are more likely to belong to. They are also more likely to have access to more candidates that you would like to evaluate and possibly give an offer, compared to 'lower end' unis.
I'm not saying that I think this order of things is jolly good, but from the perspective of this kind of business sector it makes sense. Personally I avoid finance related sectors, a stint at a casino operator to get some experience on the CV was enough for me.
I think if I want to work at Jane Street now, I either need to finish my PhD, or get a Masters degree from a sexy school to "cleanse" my WGU degree (despite the fact that I don't think I know much less than the average Ivy League graduate, though obviously I'm a biased audience).