I think it's marketing, advertising, and product refinement.
Ex: all the things Google wants your search data for.
It's somewhat silly to think the value of that data has changed much. Advertisers want to know what's popular and getting clicks and attention. Competitors want to know what features are getting used in their markets.
In the simplest case, think of this data as improving the harness, not the model.
That would be valuable to advertizers for example.