I don't think it's necessarily irrational to be afraid of the unknown. Or the known necessarily. If we're told an injection will really hurt but, we still need it done- it still feels reasonable to be apprehensive about it. How much will it hurt? Will it come with side effects?
Also- people who fear an afterlife may think the punishment for suicide may be worse than whatever other sins they committed in life. So- I wouldn't say fear of death is necessarily irrational.
But then- if you have none, I'm pleased for you. Like you say- we'll all be facing it at some point- one way or another. It's got to feel more comfortable not to fear it.
I feel like I'm mostly afraid of the dying process rather than what comes after. But, I can't say I have no fears about that too. They're just secondary.
Well injection fear is reasonable, because you can still cancel it and not do it, and any analogy in life doesn't capture the thing, because you always try to find ways to avoid pain and stuff like that if you feel like you can change it.
You can't change death in any way, it will happen whatever you do, which is the only 100% inescapable thing, so we shouldn't fear it, it is really irrational.
Because fear is really a way of trying to avoid something painful, but if you can't avoid something, then there is literally no point in fearing, its just pointless.
But I should mention that there is a thing called learned helplessness, where you feel like you cannot change things in life, so you just give up.
And in those cases they are actually actively fearing something much less than the people that don't have that condition, because you fear when you have some idea that you can change it, if you don't have that idea the fear is much less or gone.
Yeah I know that some people think that they can change what will happen after death by the way they live, but there is no basis to think that.
So we can kinda make that learned helplessness toward death, because we literally don't have any way of knowing that we change it and how to change it.
Because let's be honest, people created all this Hell and Heaven stories just to make masses behave in some controlled way.
It has nothing to do with objective reality, and there is no basis whatsoever to think that it is true.