So, this truly is a chicken-and-egg type of dilemma (though that example is actually false, as the chicken obviously came first, per Sacred Scripture).
God has permitted the Traditional movement to become fragmented precisely to reinforce in us how true it is that the Pope is the only true source of unity in the Church. Leo XIII's longer-form prayer to St. Michael (the exorcism) refers to the plan of the Church's enemies with the goal that "when the shepherd has been struck, the sheep may be scattered".
This scattering is an inevitability of this striking of the shepherd.
That's why various prophecies such as that of Anna Maria Taigi, where Sts. Peter and Paul will appear in order to designate the Holy Pope ... make a great deal of sense.
I think that Prevost could come out tomorrow denying the Holy Trinity, and the R&R and Conciliar pope-splainers, they would all find a way to claim he's still Catholic. AND, if it gets obvious enough where even that fails, who's going to organize an Imperfect Council in order to elect an actual Catholic Pope? In order for an Imperfect Council to have effect, there would have to be near-universal buy-in on it. Otherwise, it just increases fragmentation, just like when during the Great Western Schism, when they held a council to resolve the matter, it just created another Anti-Pope.
God will handle it, and we must realize that we are incapable of handling it by our own devices.
At the same time, while we will never have a practical cooperation due to too many differences, we should still be able to recongize the other groups as Catholics (with some exceptions) ... and some of that comes from backing away from the excessive dogmatization on the opposite sides, where you have dogmatic SV and dogmatic R&R polarizing everyone, and those positions are both completely false.
SVs mistake "dogmatic indefectibilism" for dogmatic SVism, and R&R dogmatize the legitimacy of the V2 popes, even though +Lefebvre never did so and was actually more a "Doubt & Resist" (which is legitimate), a sede-doubtist, as I called it.
So if the dogmatic SVs can realize that the Major Premise of indefectibility is the problem, where one might argue about the Minor (which is what +Lefebfvre did) and the R&R would realize that +Lefebvre was a doubter, and as the Canonists indicate, one may refuse submission to the Popes ...
perhaps the vast majority of Traditional Catholics can agree on a legitimate range of opinion that's still Catholic. St. Robert Bellarmine still considered Cajetan to be Catholic despite disagreeing.
There is in fact a "variation" on R&R (which should be called D&R, doubt and resist, or "sede-doubtism") that's perfectly Catholic, and it's this position that +Lefebvre actually held, and then if the dogmatic SVs can realize that one can reject the SV conclusion by rejecing one or another of the hidden (understated) minors in their syllogism, rather than the dogmatic major ... perhaps they can get to a point where, with the exception of a few outliers (such as clowns who declare Pius IX and even St. Pius X Anti-Popes), and those who explicilty reject the indefectibility of the Church, there may be some hope.
I'm trying to work on a Substack piece to explain the errors of both dogmatic SV and modern R&R (showing that it should be D&R and is what +Lefebvre believed) ... with some hope that a few might snap out of it.
We do have some moderate SV out there, and some true D&R types ... but they're drowned out by the extremes, the caricatures of their position, which contributes to and increases the polarization. R&R see SV and think of the dogmatic SV and push farther in the opposite direction. SV see the R&R types who basically deny the indefectibility of the Church, and they push back opposite of them. So when the edges are stretched like this and people are drawn toward a binary, where they must circle their wagons in one or another of these "two" camps, the polarization is intensified. And much of this is due to the fact that those on the extremes happen to be the most vocal.