Interesting point. But I don’t think you must experience something to be afraid of it, even as a population. Nobody experienced the terror of a world ending nuclear war, large asteroid strike, or solar flare (alien invasion if you want to go that far), etc. and they still terrify a lot of people. Sometimes even more than death itself.

To be more pragmatic, it’s now pretty common today for people to die and modern medicine brings them back. For practical purposes the person was dead, by some other interpretations they weren’t, if you consider the only “real” death to be the permanent one.