It recently became very real for a lot of people. The US government is buying that harmless advertising data to target, locate, and arrest/deport people. If I was an immigrant of any legal status, I would now absolutely think twice about providing a real name or address to any online service. Any benign good-faith "its only for ads" argument has been destroyed within the last year. GrapheneOS/Librem/Pursim should start advertising heavily in immigrant communities.

This also intertwines with the coordinated ID push for many social media networks. It builds an effective framework to target anyone. Trump casually designates people "terrorists" already.