The data itself has no value because it's all public/free anyway. But those who can best collect, organize and process it can sell the results of that processing for a very profitable amount. For instance, a relay can label npubs by marketing interest and sell access, not to the data, but to the labels themselves. Same for content classification for kids (pay to keep your kids safe), health metrics for insurances, etc. Super standard data pitch for VCs. 

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