Technically, ad-tracking is not an invasion to privacy per sé, and does not identify a person. It is always connected to a client, and it is illegal to connect

Technically, ad-tracking is not an invasion to privacy per sé, and does not identify a person. It is always connected to a client, and it is illegal to connect the client browsing data to a real person. So from that perspective, how is ad-tech a problem for privacy?