The court is only supposed to decide things when someone has been injured. Who was injured in this case?
The issue here is one of standing. The litigant had no standing, this case shouldn't have been heard by the supreme court. Or the hearing should have literally been "you have no standing".
Now, if congress feels like Joe Biden stepped out of line, THEY could have sued him. That would have been the proper course of action.
Here, the court has issued an advisory opinion, which is not it's role nor power. The court is out of line here.