In Oklahoma v. Castro-Huerta, the majority and dissent vigorously disagreed about the scope and meaning of federal Indian law. In particular, Justices Kavanaugh and Gorsuch contested how certain precedents, construed over the course of two centuries, should be read. Indeed, the majority and dissent bickered about what those cases actually held. One of the artifices used in these debates was the line between holding and dicta. Indeed, one of my first scholarly articles (which I never published) was on this topic. Needless to say, I am not persuaded this distinction is particularly meaningful. Rather, labeling something as dicta is a convenient way for a judge to minimize the import of unhelpful precedent.
Let's walk through the many dicta claims in Castro-Huerta
First, Justice Kavanaugh argued that the reenactment canon does not apply to dicta. In other words, Congress should not be understood to ratify statements from judicial decisions that are dicta.