As Kyle Fath explains at Security & Privacy Bytes, “the so-called ‘cookieless future’ is a result of Google’s planned deprecation of third-party cookies on its Chrome browser, which it announced in January 2020. With a significant amount of digital advertising activities being dependent on information collected by third-party cookies, Google and the rest of the advertising technology industry, as well as publishers and advertisers/marketers, are developing and seeking out alternatives. Central to the non-Google technology will be alternative ID solutions based on information other than cookie IDs, such as email addresses. Because the effectiveness of an organization’s use of certain cookie replacements, such as alternative ID solutions, will likely hinge upon the quality and amount of its first-party data, many companies are amassing troves of first-party data in a variety of ways. While Google recently announced it is postponing the end of cookies until sometime late in 2023, prudent organizations need to understand the implications of, and start to pivot towards, a cookieless future now. Cookie alternatives already exist in the market and their prevalence will no doubt increase as new privacy regulations approach and as the market responds to privacy-focused consumers and organizations.”
You can read his expert analysis of what it means going forward here.