From what I remember, those rely on some older aspects of Monero no longer present. But more importantly, they do not provide positive guidance on exactly how much mixing [churn] with what ring-sizes are needed to achieve a certain anonymity set size. Monero project itself has no statements on these key issues [except for a sentence in one of their updates stating that churning is not sufficient].
The research you linked does illustrate some problems. And Monero's reaction, to not include any disclaimers, to continue saying it is private and untraceable... misleads users.
The research you linked does illustrate some problems. And Monero's reaction, to not include any disclaimers, to continue saying it is private and untraceable... misleads users.