It may seem contentious, but how do you know this? Or do you know this? Or do you just "think" it? Or just believe it? And assuming that "inaction" is a decision wrt a set of possibilities that includes action, then inaction is just a choice of an action, yes?
I don't think there is a standard definition of inaction that is considered as correct, but I would define it as how I did in my previous post. So yes, you could say that I just believe it, at least in the situation of this situation of the trolley problem.
A decision and an action are different things. If I decide to pull the lever and save the 5 people, then I still have to physically act. If I don't decide to pull the lever, I decide inaction, but as inaction is absence of action then what remains of my choice is just the decision.
Yes, inaction in that situation, while in the common law of most English speaking countries there would be no punishment for not coming to the rescue of someone except for 2 situations, one of which I have mentioned earlier (if there is a duty to care between the 2 individuals, example: spouses have to save each other in case), would be seen as a crime in most civil law systems as you could have called 911 easily, but that doesn't apply to the trolley case. I also think that philosophically it's also different from the trolley problem. In the trolley problem you are choosing between inaction (allowing the 5 people to die) and intentionally killing 1 to save 5. Someone is going to die anyway, no matter what you choose, while with you example there is a choice in which no one will die. According to Kantianism, you would have to choose inaction, but in your example you don't have to necessarilly choose inaction as if you choose to act, no one will die.
Your example is different than the situation with the trolley case. In your case, I don't intentionally kill anyone if I choose to save one of the people drowning. In the trolley case, if I choose inaction then I just let things take their course (I don't interfere in the trolley killing the 5 people by pulling the lever and changing how things were bound to happen) so if I choose to pull the lever, I act and kill 1 person to save 5. In your case I just can save one without killing the other. He dies not because I allowed him to die, but because I couldn't save him even if I wanted. 1 person dies either way, but I am not killing the other.
I don't see why I would feel any kind of fear now while thinking what I would do if the situation was real. Fear would perhaps be able to play a role only in the real situation, if you would feel any to begin with, that is. Bystander effect is also not it, as it would only work if there are other people around you and I assumed in this situation that you would be alone in the train yard. I think a reason one would choose inaction is that there is no good solution to the trolley case. You are to choose between a minor sacrifce and a major one, and no matter what you choose you are still going to sacrifice someone. If I could, I would just go in front of the trolley and stop it with my bare hands.
Lastly, can’t the same situation be phrased either as action or non-action, or even both? Let’s say I don’t flip the switch. Phrased this way, it is a non-act. But if I say I refrained from flipping the switch, isn’t “refraining” an action? Or I can combine both phrasings so that it appears that I did both (I didn’t flip the switch. I wanted to, but chose to refrain from doing so.).
But the fact is that you still decided not to pull the lever in the end. Your final choice was inaction. Even if you were about to choose action (pull the lever), you still decided not to (inaction)