If you frame the system as "the universe conspires to create a series of coincidences such that no paradox exists", then it makes perfect sense that nobody choo

If you frame the system as "the universe conspires to create a series of coincidences such that no paradox exists", then it makes perfect sense that nobody chooses to run that experiment, because the simplest coincidence that prevents the paradox is for the characters in question to simply not think to run that particular experiment. This raises the obvious question of how the time machine got invented in the first place, which seems like a great story.