Rick Dalton said:
My only concern with the rest of that post is that Tenet is thinks they'll be destroyed immediately, but why would that be the case if the future generation doesn't plan to reverse entropy until many generations later? Sator tells the Protagonist that he believes that he's killing his son when the dead man's switch goes off and that the future generation's descendants will now be able to live. Priya also says earlier that the future is waging war against us. This post assumes there is no immediate threat from the algorithm and throws the grandfather paradox out the window.
I may be way off, but I'm thinking that in most "time travel" situations, as soon as things are in place for something to happen, it will be instantaneous because the future characters will have received that information/object and put in motion whatever the endgame is. In this case they would put someone or something into inversion and make the threat happen.