The SSPX Bishops were ex communicated under the same Canon law as the Bishops of the Chinese Patriotic Catholic church was by Pope pIus XII in the 50s, that a Bishop can not concecrate other Bishops without the approval of the Pope. As I said in a previous pope, this situation could have been rectified, by the SSPX Bishops took the difficult road that might never lead back.
Yet, some Amchurch bishops financially support and instruct CPA priests and seminarians in their seminaries and even allow the CPA priests, unbeknownst to the parishioners, to "celebrate" Mass in their diocesan churches.
And Rome remains silent, even though they are aware of it, thanks to the Cardinal Kung Foundation.
It is wrong to compare the SSPX with the CPA. The CPA openly declared themselves in schism, bragging in their written constitution that they owed no allegiance to the Pontiff whatsoever. They even usurped the jurisdictions of legitimately assigned bishops and approved publicly the Chinese government's forced abortion policy.
In contrast, the SSPX simply consecrated to protect the traditional Mass from destruction. It never usurped any bishop's jurisdiction and it has always professed its allegiance to the Pope, praying for him daily in its Masses. At the Rosary recited before Mass on Sunday in my chapel we always pray for the Pope's intentions.
Even to compare the two is ridiculous. But the double standard in the way each is treated is instructive. In fact Rome treats the CPA with far more deference--and the American Church even has amicable relations with the Chinese schismatics, though their schism is real and the SSPX's is not.