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.

>rely on some older aspects of Monero no longer present

My understanding is Monero recognized these weakness and patched to avoid them.