As it says in the beginning of the article, this study by Bp. Tissier de Mallerais was first published by the Dominicans of Avrille in 2013. The study is a compilation based on the words and writings of +ABL. It has a certain amount of Bp. Tissier de Mallerais' personal assessment or opinion of +ABL.
Bp. Fellay had the study suppressed; presumably (IMO) because it reflects what +ABL stood for, and what the SSPX of old stood for. Evidently, Bp Tissier de Mallerais had not yet got on board with the new direction of the SSPX at that time.
IMO, the bottom line of what the article says is that the Church has not defected, because there are still elements from the true Catholic Church that are present in the conciliar church.
Sedevacantists and sedewhatevers are not going to agree with it of course.
There will come a time when the idea of a conciliar church is just a distant memory, so it's good to provide a reminder by posting this article. After all, the Neo-SSPX doesn't use the phrase 'conciliar church' anymore. They say 'official church' instead.
Sedevacantists dominate tradition outside of the SSPX, and they don't believe in the idea (for the most part) of a conciliar church, so eventually, there will be few who will still understand what it means.