Yes, if sede-ism was actually true, they would have correctly elected a Pope decades ago, and he would have received universal acceptance. The Pope receiving universal acceptance in the Church is the work of the Holy Ghost. When God does not approve of an election, He will not give UA.
Here's why the situation doesn't resolve for the sedes: Only the Roman Clergy strictly have the right to elect the Roman Pontiff. But only the Roman Pontiff can appoint or incardinate Roman Clergy, among whom the Cardinals are the chief. Thus, the sedes are looking for Roman Clergy incardinated into the Roman Church to whom they can say "you are the electors of the Pope". But all those electors recognize the Pope. +ABL said, "The subsequent unanimous acceptance of the Cardinals and the Roman Clergy suffices to validate it (the Papal election). That is the teaching of theologians". So, sede-ism will go nowhere until they have Roman Clergy, which they don't.
The very fact that all the Roman Clergy recognize the recent Popes should be, as +ABL said, a sufficient proof that they are the Popes.
Next, some sedes will claim, if the Roman Clergy don't elect, then - supposedly - any group of Bishops, even vagrant Bishops without ordinary jurisdiction - again supposedly - can get together and elect. This too leads to stalemate, because no one knows who these Bishops are, how many there should be, what agreement is sufficient etc. And all that besides the fact that the SSPV, CMRI etc don't work together and SSPV believes CMRI and Thuc line orders to be invalid. If Christianity depended on sede-ism, Christianity would end.
All this because of simple unwillingness to accept the Dogma of Perpetual Papal Successors and acknowledge the plain fact that the Popes have truly been Popes.