Topics essentially works like this: rather than using cookies to track people around the web and figure out their interests from the sites they visit and the apps they use, websites can ask Chrome directly, via its Topics JavaScript API, what sort of things the user is interested in, and then display ads based on that. Chrome picks these topics of interest from studying the user’s browser history.
Isn’t this completely immoral? They are literally stealing the users private browsing history and uses it to boost their own profits.
So this is why they want that browser integrity stuff.
Without the integrity a change like this would be absolutely wonderful - my ad interests would be “FuckOff” and “Nothing”.