The comments I am reading here seem to imply that this is more privacy invasive than tracking cookies. Steve Gibson did an analysis on Topics and his conclusion was that this is an approach to provide targeted ads (which websites need to make money) without being invasive.
Although if you believe that being online you should be 100% anonymous and share 0% of personal data then of course Topics is not good (but then no other ad targeting solution will be either).
Here is a link to his podcast where he explains the specification: https://twit.tv/shows/security-now/episodes/935?autostart=fa...
Although if you believe that being online you should be 100% anonymous and share 0% of personal data then of course Topics is not good (but then no other ad targeting solution will be either).