pseudo anonymity != pseudonymity. In laymans terms, "pseudonymity" means "fake name" whereas pseudo anonymity would mean "fake anonymity". shemnon42 is using the exact terminology you are referring to.

In this case, the conventional definition of anonymous is less useful than domain-specific definition of anonymity, since different currencies have different levels of anonymity. Recent HN discussion: https://news.ycombinator.com/item?id=14672691