“The creation of other Latin Mass orders can be traced to the work of the SSPX...”
Especially their disobedience.
“Whatever - the fact is that the SSPX has done more to preserve and pass on the very real traditions of the Church than any other organization.”
Maybe. The other side of that coin is the sedevacantism they publicly denied but fostered in their seminaries nonetheless. Without SSPX there would be no SSPV, nor CMRI, nor two or three hundred other groups around the world which have separated themselves from the Church.
Be fair to SSPX. They are good. . . and bad.
The sedes are few and far between. The ICK, the FSSP and the Personal Apostolic Administration of Saint John Mary Vianney are thousands of times larger.
I think the sede movement may grow again though as people realize that we may have an anti-pope brewing.