All the argument shows is that ordinary people never assign to events enourmous utility values with also assigning them commensuably low probabilities.
Under certain assumptions (which perhaps could be quibbled with), demanding that utility values can’t grow too fast for expected utility to be defined actually does imply that the utility function must be bounded.
Under certain assumptions (which perhaps could be quibbled with), demanding that utility values can’t grow too fast for expected utility to be defined actually does imply that the utility function must be bounded.
I’m not sure what you mean by that.