Here is an example. This page [1] has stuff from google loaded that is not blocked by a combination of Ublock Origin and Privacy Badger; for instance google fonts (other stuff from Google, Twitter and Facebook is blocked). If I ever log into Google, then my activity on this page will be linked to my account. If I containarize my Google account, then I guess Google can only use my IP or very advanced tricks to attach this activity to my account.

[1] https://www.sportsbettingdime.com/news/nfl/week-7-opening-li...