Death Grips is simply the latest addition to the ridiculous discography (check out those performance credits) of Zach Hill, originally of chaos-instrumental-pop group Hella. You should also scope out Nervous Cop featuring members of Deerhoof and a peep at a pre-Milk-Eyed Mender Joanna Newsome.
I would definitely assume that this is mostly his doing, he's very good at picking the best people to work with, making them be weird, and drawing out their best efforts.
My axe to grind with Death Grips is that their first album is scattered affair that borderline steals scenes directly from Food for Animals (2008, dude) and my very good friend, who is very well known in some "underground" (for lack of a better term) circles, BLACKIE, who has been digging in this crate for a loooong time.
In the summer of 2010, in the tail-end days of the "chillwave" thing, he and the band I was in at the time went on tour on the east coast. We got added onto one of the Brooklyn rooftop parties when those were starting to go strong. He has a very cathartic live presence and encourages the crowd to get rowdy, so some people out of the 300-400 people there did, but the rest just bolted and made a giant circle, staring at him like he was an alien. I saw some blog posts later with comments like "wtf was up with the rapper dude?" "that was the worst show ever" etc. He gets off to this and is used to it, so no biggie.
6 months later, this video comes out, a few months after that, Exmilitary drops, and all of the sudden, the noisier and weirder the hiphop, the better. My friend hasn't been swept up in this wave, other than some producers in NY hit him up pretty often, wanting to make music with him, but he's always been a lone wolf.
He was supposed to do some shows with DG, they cancelled on him and never tried to organize anything else, the dudes from clipping played a show with him and told him he was one of their primary influences, there are rumors that Kanye was listening to BLACKIE, amongst others, when he was getting inspiration for Yeezus (tho that album is more so indebted to my one true love, Arca), but he's still not really gotten much bigger.
Granted, noisey hiphop has been around for a long time, there's plenty of reason to believe the DG was the logical conclusion of all the members well before they started this project, but they still owe my man a favor, imo. At least tour with the dude that was hashing out this genre well before it started getting polluted.