Sedevacantism is an attempt to answer a question that is not in the realm of the faithful to answer. Nor to solve.
You build other things around it, like justifying attending Thuc line Sacraments, and attack the resistance, because they are a threat to you.
A large number of sedes are troubled people. Some are autistic, and others are plain prideful. But not all. some are perfectly reasonable people. However the theory, usually leads to other mad theories, and this bad fruit is something to take note of for a discerning person coming from the Novus Ordo, or thinking about converting to Catholicism from something else. 400 Thuc line bishops says it all really. Not to mention God only knows how many "Popes".
So if you want to have it as a theory, like Father Ringrose or many other resistance priests, then fine. But the second you start going down other mad rabbit holes then I say stop. Examine your conscience, focus on other things in your life that dont involve posting on the internet like some moron who thinks they know better than everyone else.