The objection that Roberts raises to the reasoning in Dobbs is that it goes further than Roberts believes necessary. He’s willing to uphold the Mississippi law but he would just update the Roe/Casey mess with another rule. He agrees with the critique of Roe by the majority but doesn’t want to get rid of a constitutional right to infanticide. Rather than right a wrong decision, Roberts would rather make the decision only a little less wrong.
I don’t believe I’ve ever seen a Chief Justice’s opinion get a smackdown like this from other members of the majority he joined. Justice Alito succinctly summed up Roberts’ approach: “The concurrence’s most fundamental defect is its failure to offer any principled basis for its approach.”
Roberts’ concurrence reads very much like that of a man who has lost control of the Court and the respect of his colleagues. The only reason I can see that Roberts concurred with the opinion is that he didn’t want to be repudiated by the Court in what will likely be the most significant decision of his tenure as Chief Justice.
The bottom line is the justices of the SCOTUS conservative wing don’t trust him and don’t trust his finger-in-the-wind incrementalism. The Court is clearly being led by the Thomas-Alito partnership that is providing the willpower and guts to motivate the conservative majority to decide cases based on the law and not worry about what the editorial boards of the Washington Post and New York Times say.
This.
They have filled Scalia's big shoes nicely.