[II2II]

What does having enough time actually mean? I am almost certain that I would freeze if I encountered such a situation in real life, or panic and be unable to figure out how to flip the switch ...

... which brings up the real problem with these scenarios. In real life, the person at the switch would be trained. While that training is unlikely to include hypothetical scenarios created by philosophers, they would be expected to assess the safety of the act. This would put them into a position where the physical act of pulling or not pulling the switch would not, as you say, make much of a difference. They would have to answer for their actions down the line, even if their only answer was that it put them into an ethical conundum where they had insufficient information to assess the value of that one life verses five. A court may, or may not, accept that argument. It could be based upon the numbers (e.g. five lives are more valuable than one). It could be based upon the psychological impact of the decision upon the switch operator (e.g. a calculated sacrifice of one life may be frowned upon relative to an emotionally crippling indecision that led to the loss of five lives).

In turn, that brings up another issue with these artificial scenarios: they virtually always include follow-ups that are intended to raise doubt in decisions made. What if that one person was a child with their entire life ahead of them, and the five lives elderly people who have less to look forward to? What if that five included a "Hitler" plus four regular people, and the one was a "Gandhi" (i.e. the one slaughtered many orders of magnitude more people, and the one was revered for their regard of life)? Those are the sorts of things that are usually raised to justify indecision, even though they are highly unlikely.