The Judge spent the time to do exactly this. Judges are busy. Their time is valuable. The lawyer used AI to make the judge do work. The lawyer was too lazy to do the verification work that they expected the judge to perform. This speaks to a profound level of disrespect.
I highly doubt the judge was tracking down citations or reading those cited cases herself to verify what was in them. They have law clerks for that. It doesn’t make it any less an egregious waste of the court’s time and resources, but I would be surprised if a district court judge is personally doing much, if any, of that sort of spadework.