ohduran probably means that there is no a priori logical reason for the two to go together. In theory they could be separated. However, it is far too enticing of a profit opportunity to use aggregated data if one has it en masse to sell personalized data.

I happen to disagree; almost any for-profit business is going to be doing some sort of aggregated usage data. I mean at the most basic level they've got to be tracking the number of customers they have. That doesn't mean all for-profit businesses ultimately devolve into data selling businesses.

Although perhaps ohduran is advancing a more nuanced argument. In particular perhaps the more detailed usage data you track, the more likely the siren call of selling that data is to be attractive. In order to compete with Google on search quality, perhaps you do need sufficiently detailed usage data that the call becomes irresistible.

I'm still not convinced that's true, but I could see how it plays out.