OSINT (not a term I was particularly familiar with, personally) actually goes back quite a ways[1]. Software certainly makes aggregating the information easier to accumulate and finding signal in the noise, but bad security practices do far more to make that information accessible.

[1] https://www.tandfonline.com/doi/full/10.1080/16161262.2023.2...

Back in the 1990s my boss went to a conference where there was a talk on OSINT.

She was interested in the then-new concept of "open source" so went to the talk, only to find it had nothing to do with software development.