Dred Scott legislated the repeal of the Missouri Compromise just as surely as if Congress had voted to repeal it. But Congress didn't.
If you don't say (as the court didn't in Korematsu) that the other branches of the government have to live up to the law -
fiat justitia ruat caelum - that is
changing the law.
If you interpret "public purpose" as meaning "for the benefit of a private property developer" (as the court did in Kelo) then you're rewriting the law with a bucket of whiteout and a fat Sharpie.
Roe was a disaster for public health. At the time, many states were quietly decriminalizing abortion. Now, because Justice Blackmun thought nine years as counsel for the Mayo Clinic gave him the authority to write laws regulating the practice of medicine, such a hornets nest was stirred up that abortion clinics are literally under siege (I found a list of six states that, as of 2019, had but one abortion clinic still open!)