This is not the teaching of the Catholic Church and has never been. The Catholic Church has always condemned schismatics and schisms. That remains in effect.
However, the current Orthodox Christians are not schismatics. Their anscestors who broke with the Church of Rome were. The anathema and condemnation, and excommunication applied to them. This is why Paul VI lifted the excommunication of the Orthodox Christians, because it was not fair to hold them accountable for a schism that was caused by their anscestors and ours.
By orders of the Holy See Catholics must accept the Orthodox Churches as Sister Churches, while still holding that the Catholic Church is the Mother of the Churches and the only one that has the Petrine succession and also has the place of primacy.
The Orthodox Patriarchs have accepted that the Bishop of Rome is the legitimate successor of Peter. The issues that are being discussed are the primacy of Peter among the Apostles, the infallibility of Peter and whether Mary was conceived without orginal sin or born without original sin.
Theologians on both sides have been working for years to understand each other and have made significant progress. They have agree that the problem begins with hermaneutics rather than ill will on either side.
In the case of SSPX the Archbishop and the bishops that he ordained were excommunicated as were the original patriarchs of the Orthodox Churches, for the same reason, disobedience. There is no change in policy and practice.
In addition, the Orthodox Churches were founded by the Apostles. SSPX was not. The Orthodox Churches have direct appostolic succession. The SSPX has apostolic successiong in sacris. The Archbishop was a valid bishop and the SSPX bishops are validly ordained bishops. The Sacrament of Holy Orders within the SSPX is valid, though ilicit.
In the Orthodox Churches, the Sacrament of Holy Orders is not ilicit. They did not need the permission of the Pontiff to ordain bishops. They had that permission from the Apostles and the Pontiffs that succeeded Peter.
To conclude, John Paul II says in Ecclesia Dei
**3. In itself, this act was one of disobedience to the Roman Pontiff in a very grave matter **and of supreme importance for the unity of the church, such as is the ordination of bishops whereby the apostolic succession is sacramentally perpetuated. Hence such disobedience - which implies in practice the rejection of the Roman primacy - constitutes a schismatic act.(3) In performing such an act, notwithstanding the formal canonical warning sent to them by the Cardinal Prefect of the Congregation for Bishops on 17 June last, Mons. Lefebvre and the priests Bernard Fellay, Bernard Tissier de Mallerais, Richard Williamson and Alfonso de Galarreta, have incurred the grave penalty of excommunication envisaged by ecclesiastical law.(4)
The crucial problem here is that this constitutes a grave act of disobedience.
JR