Only a small fraction of Netflix subscribers are cord cutters. They will undoubtedly see a benefit (short term) of this move. Long term internet TV is going to be a lot like cable TV is today. There won't be aggregator services. Starz will have it's own "app" on all of these boxes that you subscribe to outside of Netflix. NBC will probably have their own as well. CBS will be one of the last holdouts, their audience is old enough that the internet is having a softer affect.
Us early adopters have had it really good for the last few years, surely you didn't think it was going to continue? Surely you didn't think you'd be getting a large and continually growing catalog of movies (many of which are fairly recent) for only $8 a month forever? Like it or not but businesses like Starz hold all of the cards.