The “quad box” is the killer feature on Fubo, my TV provider of choice, and it’s coming to YouTube TV just in time for its integration of the NFL Sunday Ticket package. Given Apple’s investment in MLS, it makes sense there. Sports is the perfect application for watching more than one live channel at a time.
In the long run, though, this needs to be a tvOS-wide feature. Right now if there’s a game on Fubo and another on ESPN+ and a third on MLB and a fourth on the TV app… I can watch one at a time or, if I am very lucky and it’s the right combination of apps, two at a time—one in a tiny picture-in-picture view. The OS should put it all together. Maybe this is a step in that direction… or maybe it’s just something Apple had to build for MLS. I hope it’s the first one.