"Unfortunately the author was typical of the 'true believers' in the SSPX who think the SSPX the Catholic Church - in other words no one else"
Although there may be some misguided individuals out there who behave as if "outside the SSPX there is no salvation", most Catholics only turn to the SSPX for refuge in the modernist storm - realizing that it's certainly not a perfect society - but better than other available options. These are perilous times, and with much of the Church in open apostasy, let's not despise those families who seek solace with the SSPX, and let's hope they don't despise others who take a different route e.g. the "indult" option.
The problem is when they are basically taught from the pulpit "Extra SSPX Nulla Salus". I am calling to task the SSPx itself, the clerics who are its superiors and those of its priests, not all by any means, who attempt to indoctrinate the same insanity in its laity.
If the laity start believing this themselves then they are to be pitited because they are in for a rude awakening.