I worked on Ad systems for 2-3 years. It is fault of advertisement industry and RTB. RTB rely on personal data with some fields missing (name, phone, email, et

I worked on Ad systems for 2-3 years. It is fault of advertisement industry and RTB. RTB rely on personal data with some fields missing (name, phone, email, etc) to be send for real time bidding for Ads by many players. Remaining data mapped by these players to infer these missing fields and guess purchase habit of person browsing the site and bid on Ad space. Data sent to these RTBs do have unique fields like Android Ad ID that can easily identify person. Ad industry rely on these obfuscation like Android Ad ID to track us individually but giving the idea that personal data is not sent.