Eh, this was always on shaky legal grounds. Even Pelosi herself said last year that she didn't think the Executive had the authority to unilaterally do this, and as I understand, Biden was skeptical as well. It's a bit of a stretch to say that Congress intended to allow the President to unilaterally void student debt when they passed a measure to allow for adjustments during emergencies.
The ostensible textualists on the Court are certainly being a little hypocritical, but it's not an absurd ruling.