It may indeed kill it, but I'll just start my outcry right now: streaming will not happen for me, ever, unless I'm capturing it to burn to disc, and there's no other option.
You can take my physical media when you pry it from my cold, dead hands.
At this point in its life cycle, streaming is for people who think it's really neat to watch movies on a postage stamp. That may change, but I also think that the general public is totally fine with compression artifact-ridden garbage being sold to them as high def content. And of course when everything is in the cloud, the whole concept of individuals owning their movies will be a polite fiction at best.