If that didn't drive the point home, the occasional Soviet space disaster certainly would have.
More importantly, everyone of them expected 'You're going to burn-up and die in launch/re-entry/all your air vents in space/your engines will misfire, and you won't return home' as big, serious risks of their work.
Nobody expected 'You're going to burn-up and die as a result of getting into a closed room, and pushing a few buttons', to be in their top-ten expected causes of death. Planning around unknown unknowns, and all that.
As a sidenote, it wasn't a Saturn V.
Going to space involves strapping yourself into a tiny capsule on top of something that's filled with explosives. There's nothing safe about it.