Are unlimited data plans driving mobile-first streaming or are the rise of OTT video services driving the popularity of unlimited data plans? Either way, so-called unlimited packages have made limiting mobile data usage a necessity for MNOs, with Comcast the latest to be the bearer of bad news for mobile streaming fanatics. The Xfinity Mobile MVNO venture, piggybacking on Verizon’s network, will soon be reducing video quality from 720p to 480p when streaming content via mobile data. Of course it tries to use WiFi offload most of the time. Once unlimited Xfinity subscribers exceed their 20GB monthly data caps, download speeds are restricted to 1.5Mbps and upload 750Kbps, while streaming over WiFi will remain unchanged as standard. In addition, “if…