There is a world wide effort to restrict religious liberty, to put the government power over the Churches. In many countries the Catholic Church, and other churches, are striving to support churches and clergy in any way they can. Baptists sometimes support Methodists, etc. “If we don’t all hang together, we will all hang separately”.
In Argentina there is apparently a restrictive law on “unrecognized” clergy, that they can be briefly deported at intervals, then quickly readmitted to the country, all of which would Eco be time consuming and expensive. The Catholic Church certified SSPX clergy as Catholic, partly as an act of charity, but also to avoid the precedent of any clergy being persecuted. They would likely have done the same for others, if necessary. It is not a lie, of course SSPX individuals are Catholic. The Church still has the spiritual and material welfare of individuals in SSPX at heart.
BTW, I know the SSPX favors religious liberty. They may occasionally take some public actions, on their own. But they aren’t united to the larger religious liberty effort, in my diocese, or nationally, to my knowledge, at least in my country.