I can’t take seriously the opinion of those who discard a teaching (universality of time) which goes all the way back to Scripture (“Though we or an angel from heaven preach to you a doctrine other than that which you have received, let him be anathema.”).
If you would discard antiquity as a criteria for magisterial teaching, why wouldn’t you discard the popes?
But there is little doubt that Viganò has hit upon something new: The idea of a false council.
In this regard, sedes appear not to notice (or simply disregard) the dangerous terrain they have entered:
1) A pope’s disavowal of infallibility amounts to nothing;
2) By jettisoning universality of time, they reject a teaching contained in Scripture, the Fathers (St. Athanasius, St. Vincent, et al), and countless popes and approved theologians, and pave the way for every novelty to be considered Catholic.
Contrarily, Viganò seems to have discovered the solution to the recovery of orthodoxy:
Lacking these two criterion, any alleged council would not be authentically ecuмenical.
This would be a substantial development of doctrine in ecclesiology (ie., How the Church understands or validates or rejects councils).
Now I am also considering a new argument:
Dogmatic fact:
All other councils were clearly dogmatic facts PRECISELY because they were infallible and universal (spatial AND temporal).
But Vatican II was neither.
Therefore, the teachings of Vatican II are not dogmatic fact.
But the manuals all list ecuмenical councils as dogmatic facts.
Therefore Vatican II was not a true ecuмenical council.
Ps: Please note I am still merely troubleshooting Vigano’s ideas here, not stating things as fact and conclusive.