The canon doesn't say that the Mass will always be perfect and a great expression of the Catholic faith. All it says is that the Mass will not be an incentive to impiety. The Novus Ordo Mass, in the original form, consists of bible readings, a consecration and prayers. Sure they're bland and stripped of a lot of Catholic content but nothing in it is actually heretical.
Great heresies have started before from the change of only one word! It could be heresy but just not dogmatically defined as such yet. Is heresy not "stripping" some Catholic doctrines but keeping others? You could possibly say the same thing about some Lutheran service books. Heresy not only about what is say, but what is NOT said as well.
"“If anyone says that the ceremonies, vestments and outward signs, which the Catholic Church uses in the celebration of Masses, are incentives to impiety rather than the service of piety: let him be anathema.”
Can someone tell us what "ceremonies, vestments and outward signs" found in the actual Missal of Paul VI are incentives to impiety?
The Missal itself though at least seems to have destroyed the faithful's piety though, for its consequences are what is going on today or at least what may be its consequences. There's no doubt that according to a very holy Cardinal and former Prefect of the Holy Office that even the original Latin new Missal "represents, both as a whole and in its details, a striking departure from the Catholic theology of the Mass as it was formulated in Session XXII of the Council of Trent" and that "the "canons" of the rite definitively fixed at that time provided an insurmountable barrier to any heresy directed against the integrity of the Mystery". Is it not heresy to desire to, and to, take away from the Missal prayers that are an insurmountable barrier to any heresy against the Mass?