[Question] The unfalsifiable belief in (doomsday) superintelligence scenarios?

Having read Bostrom’s superintelligence book and a couple of adjacent papers by him and Yudkowsky. There is no clear line of argument from beginning to end but rather a disjunctive list of possibilities that all lead to similar extinction events. This leads the entire theory to not be falsifiable, cut off one road toward superintelligence or a related extinction outcome and a new one will pop up. Whatever amount of evidence mounted against it will never be enough.

Is there an existing response to this problem that someone could point me to? Either the unfalsifiability not being a problem or some key detail in the argument that I have missed.