"But for all bittorrent's success, Netflix (and others), which are centralized and highly controlled alternatives, are far more popular and commercially successful for watching online video -- it is just less work to use Netflix, even though it doesn't have the benefits of being free and open."
What about skype, that was built upon supernodes, and was decentralised?
Skype was never radically decentralized -- it was a managed centralized/decentralized network. Its decentralization was to offload costs onto users to provide a cost advantage compared to running a lot of centralized hardware, but otherwise it was centralized.
Skype accounts were centrally registered and a single company was responsible for network health, security, etc.
What about skype, that was built upon supernodes, and was decentralised?