I guess the thing I notice most here is the fact that it was a big surprise that Netflix made such a bone headed maneuver. This just demonstrates that we are all vulnerable to making mistakes. So often I see people in the tech industry and business in general mistake luck for competence. In isolation or without wise counsel, we all make mistakes and sometimes they are huge.
You could have asked almost any Netflix subscriber if it was a good idea to split the services, increase the fee by 100%, and change the web site and brand name. Any of them would have told you it was a terrible idea, but on a spreadsheet and marketing presentation it probably sounded brilliant.