The ruling of the Grand Chamber of the Court of Justice in Case C-118/20 JY v. Wiener Landesregierung EU:C:2022:34 follows the judgments in Rottmann and Tjebbes. These cases concern the relationship between EU law and national citizenship. In particular, they deal with the compatibility of national authorities’ decisions on loss of nationality with the proportionality principle. The JY v. Wiener Landesregierung case highlights the contradictory nature of nationality law, which cannot be fully understood from a purely domestic perspective and yet remains within the sphere of Member States’ competences. Overall, the decision of the CJEU in JY v. Wiener Landesregierung leaves a bittersweet taste in EU lawyers’ mouths. On the one hand, the Court appears to implicitly make clear its aversion for certain national practices. In doing so, it ensures, in the case in question, a higher degree of protection of EU law-derived rights. On the other hand, the ruling does not adequately ensure sufficient safeguards for similar future cases. Finally, the Court seems to have missed a significant opportunity provided by the principle of mutual trust.