Well, that stdio thing is actually what I love about Hacker Rank :)
I don't think the boilerplate code is a problem, if you use a reasonable language. Racket is a pleasure to use over there, Clojure slightly less so but wouldn't call it irritating...
I was thinking the same question and the reply would probably be "performance". I don't think untyped Racket can currently compete with SBCL and I'm not sure they'd be interested in Typed Racket. But I'd love to be proven wrong on both of those things ;)
I'd like to join a company where I could let loose my love for data and functional programming - with lots of parentheses, preferably :) I'm currently working in a data science team in a major pricing science company, applying algos to heaps of transaction data in order to find out how to make more money on B2B transactions. I know some ML basics and I'm actively learning more.
I'm not able to relocate but I have a firm grip on remote working as I've been working remotely for a few years now. I'm OK with visiting your HQ like two times a year or something like that...