They are routinely thrilled when it's law passed by the courts in their favor. The court has made a bewildering set of rulings on gerrymandering whose only commonality is they they always favor Republicans.
So not exactly bewildering, I personally saw it as closer to inevitable. The Supreme Court never had the power to legislate, it can only interpret, and a shaky interpretation always has an expiration date no matter how popular it is.
The court invalidated part of an existing law passed by Congress, it didn’t create a national framework in the absence of any law never passed by Congress