So on one hand you say that SSPX is not against Feeneyism and on the other you say even if they are it does not matter.
Father Feeney's
Bread of Life has not been condemned, and individuals who support that POV are free to receive and give the Sacraments within the Catholic Church, or at least the
Novus Ordo Church. Of course, with no true Vicar of Christ on the Throne (or so say the sedes), all that you can appeal to is
private judgment. Even the last true Pope (in your view), Pope Pius XII did not condemn "Feeneyism" and neither did the Holy Office Letter even condemn it. The only condemnation in that docuмent is the following:
Furthermore, it is beyond understanding how a member of a religious Institute, namely Father Feeney, presents himself as a "Defender of the Faith," and at the same time does not hesitate to attack the catechetical instruction proposed by lawful authorities, and has not even feared to incur grave sanctions threatened by the sacred canons because of his serious violations of his duties as a religious, a priest, and an ordinary member of the Church.
Again, what "grave sanctions" did Father Feeney incur? As we all know, he was excommunicated for
disobedience and not for heresy. And, yet, he was reconciled by Pope (or, anti-Pope) Paul VI without ever retracting his former "errors". So, where are things today? You cannot say for certain, because, in your view, the Chair is empty.