While I obviously disagree with the decision on principle, this is actually on balance good for Democrats. The North Carolina map will likely be struck down by the state Supreme Court now, while the Maryland map is safe.
Maybe in the short-term. The long-term would have been much better for Democrats if partisan gerrymandering everywhere was reigned in. Although tbh it's debatable how much, because even a favorable decision here probably would have only curtailed the more extreme maps.
edit: Actually, maybe not. Not sure how Ohio, Michigan and North Carolina's cases would have gone, but if all 3 had to be redrawn, that would have better for Democrats (even if MI doesn't change much).