I agree with most of your post, but I still think that most of the "data science advantage" you assume drives the success of services like Google and Netflix is just good old network effect at work.
Example: the recommendation engine in Netflix is mediocre at best, and in my 3+ year as a user I never gotten any useful suggestion out of it. What they do have is Breaking Bad, House of Cards and a lot of other movies I wanted to watch. If they lost their good content, I wouldn't think twice about canceling, data or not data.
I think you're right that data is not the only moat, but it definitely helps. I think it's also important to separate personal preferences from the general public (something I've learned and re-learned as a VC). That is, you might go to Netflix for specific/great content -- and I do, too -- but lots of people will just watch whatever Netflix recommends because the recs are good.
