Benedict XVI really, really, wanted to reconcile SSPX with Rome. And after a couple of somewhat pugnacious SSPX leaders.......ahh........moved on, it looked as though things were going that way. When Pp. Francis was elected, early statements from his peeps led many to believe that the long-awaited reconciliation was imminent. After all, Francis had reached an informal accommodation with SSPX while he was primate in Argentina, right??
Well, don't open that bottle of Lafitte Rothschild yet.
...During the meeting with the Roman authorities, it was recalled that the fundamental problem is actually doctrinal, and neither the Society nor Rome can escape this fact. Because of this irreducible doctrinal divergence, for the past seven years no attempt to compose a draft of a doctrinal statement acceptable to both parties has succeeded. This is why the doctrinal question remains absolutely essential.