The idea that "stop the trolley" or "slay the dragon" is cost-free is a wish. You've merely added a third horn to the dilemma. "Someone brave attempts to jump onto the moving trolley, risking their own neck" might well be the preferred choice; the expected outcome may marginally improve; the shape of the problem remains.
I hope you're arguing out of perversity, not conviction - such is valuable, and i did have to think for a minute. I agree that lateral thinking can be productive.
At no point did I say anything was "cost-free" or even make any reference to cost. It's extremely rare for the cost of an action to be at all relevant to its morality.
> Someone brave attempts to jump onto the moving trolley, risking their own neck
This is a completely different problem. The whole point of the trolley problem is to attempt to justify the sacrifice of the few for the good of the many.
The entire framing is about other people dying, not whether or not you would sacrifice yourself.
I hope you're arguing out of perversity, not conviction - such is valuable, and i did have to think for a minute. I agree that lateral thinking can be productive.