A friend and I used to run a website that tracked activist short sellers and their campaigns, and published all that information as a nice centralized database basically.
Hedge funds were, by far, the most interested in this - which was surprising to us, our original target audiences were auditors and legal firms. My impression from this experience is that the more successful hedge funds are just mass-ingesting data from everywhere they can, and somehow trying to make sense of it.
It's totally an arms race too: Once one of them is ingesting data from a new source, everyone else has to start doing it as well lest they fall behind. It was significantly easier to convince new clients once we had a few clients already (very much like the FOMO people speak about when fundraising).