From yesterday on HN:
https://news.ycombinator.com/item?id=21606415
Personal and social information of 1.2B people discovered in data leak
Fourth paragraph of the story:
For a very low price, data enrichment companies allow you to take a single piece of information on a person (such as a name or email address), and expand (or enrich) that user profile to include hundreds of additional new data points of information. As seen with the Exactis data breach, collected information on a single person can include information such as household sizes, finances and income, political and religious preferences, and even a person’s preferred social activities.
Each time a company chooses to “enrich” a user profile, they are also agreeing to provide what they know about the person to the enriching organization (thereby increasing the validity of the organization’s future results). Despite efforts from social media organizations like Facebook, the resulting data continues to be compounded, creating a situation with no oversight that ultimately allows all of a person’s social and personal information to be easily downloaded.
https://www.dataviper.io/blog/2019/pdl-data-exposure-billion...
Extrapolate present AI, facial-recognition, location tracking (cell phones), voice-recognition, and integrated databases. You're already 99% of the way there.