Deanonymizing people across datasets for one. Maybe attacker or maybe next gov that goes full Hitler and subpenas tech companies to introduce social karma and

Deanonymizing people across datasets for one. Maybe attacker or maybe next gov that goes full Hitler and subpenas tech companies to introduce social karma and you are put on a no-fly list because you expressed interest in UK royalty or have a cousin in Iran. Invisible bubble and radicalization for another.