Archbishop Lefebvre did very well when he refused the agreement.

"For what participation hath justice with injustice? Or what fellowship hath light with darkness? And what concord hath Christ with Belial? Or what part hath the faithful with the unbeliever?" (2 Cor. 6, 14-15).

Francis did not restore the title "Patriarch of the West" at all. He simply included it in the list of so-called "historical titles" of the Popes. In fact, Francis renounced all these titles (including the title of Vicar of Christ) as confirmed by Cardinal Cantalamessa:

"Ho notato con gioia che nell’Annuario Pontificio, sotto il nome del papa, c’è il solo titolo “Vescovo di Roma”; tutti gli altri titoli – Vicario di Gesú Cristo, Sommo Pontefice della Chiesa Universale, Primate d’Italia ecc. – sono elencati come “titoli storici” alla pagina seguente. Mi sembra giusto, soprattutto riguardo a “Vicario di Gesú Cristo”. Vicario è uno che fa le veci in assenza del capo, ma Gesù Cristo non si mai assentato e mai si assenterà dalla sua Chiesa. Con la sua morte e risurrezione, egli è divenuto “capo del corpo che è la Chiesa” (Col 1,18) e tale continuerà ad essere fino alla fine del mondo: il vero e unico Signore della Chiesa".

From this document:
"The Catholic Church has always held that popes can be heretics, and that a pope who commits the public crime of heresy loses the papal office thereby. This belief is based on the teachings of the Scriptures, which assert that the heretic separates himself from the Church by committing the sin of heresy.
...
Theologians and canonists have disagreed on the details of how a heretical pope falls from office".

Well, based on what was said in the first paragraph, the authors of the document, if I understood them correctly, still reached a consensus that Francis, being a public and notorious heretic, fell away from the Church according to Divine Law. The only difficulty (noted in the second paragraph) is the question of how to remove a heretic (who has already fallen away from the Church) from the position he occupies. It seems to me that despite the difficulty noted, consensus on the first point is important.