I agree with the spirit of your article. But the Constitution does not say abortion is a state decision. It says nothing explicitly about abortion. As with so many SCOTUS decisions, the Court interprets what the Constitution says since the Constitution can’t possibly address every contemporary issue. The Justices often claim their opinions are based on the Constitution. A lot of the time, this is hogwash. SCOTUS is political. They make ideological decisions. In my opinion, few of their decisions have anything to do with the Constitution, which they use to make their political decisions more authoritative.