If you have a system in which a single failure could mean extinction of anything very important, then it seems likey that there must have been many failures in safety systems and backups leading up to that situation—which would seem to count against the idea of a single failure. We have had many millions of IT failures so far already.
If you accept that a single failure could mean extinction and worse the history of rockets and powered flight isn’t exactly inspiring.
If you have a system in which a single failure could mean extinction of anything very important, then it seems likey that there must have been many failures in safety systems and backups leading up to that situation—which would seem to count against the idea of a single failure. We have had many millions of IT failures so far already.