it should be willing to pay pC to get the same benefit with probability p.
This was about real people, not ideal utility maximizers. Even if one agrees with “it should be willing to pay pC to get the same benefit with probability p”, which most risk-averse people won’t, “Any and all cost” does not mean infinite cost to most people (sacrificing their firstborn is probably not on the list, neither is killing the rest of the humanity).
If you want to question the assumption that’s fine (I agree that people don’t really want it at literally any cost), but don’t complain that I gave the explanation you said you didn’t see of how the assumption implies the conclusion.
This was about real people, not ideal utility maximizers. Even if one agrees with “it should be willing to pay pC to get the same benefit with probability p”, which most risk-averse people won’t, “Any and all cost” does not mean infinite cost to most people (sacrificing their firstborn is probably not on the list, neither is killing the rest of the humanity).
If you want to question the assumption that’s fine (I agree that people don’t really want it at literally any cost), but don’t complain that I gave the explanation you said you didn’t see of how the assumption implies the conclusion.