Thanks for posting such a detailed response!

It didn’t occur to me to distinguish between Thing One and Thing Two, and you’re right that they’re qualitatively quite different, but it shouldn’t make too much of a difference quantitatively. This is because the Thing Two number is basically derived from Thing One estimates, except that everyone is assumed to have the same value-of-life as a “representative” person. Thing One studies do produce values in the range of $6M.

someone sufficiently poor will get zero or negative utility

In reality, very poor people do try to stay alive, so any model that assigns them negative utility is incorrect - it’s a good sanity check to verify that this isn’t the case. The model I gave in the post suffers from this problem. However, a model where utility becomes utility at low incomes is not necessarily incorrect! Since there’s a minimum income required for survival (actually a minimum consumption level, since other people can give you free stuff, but I’ll ignore the distinction since this is a toy model), very few of the observed poor people will have income smaller than that, since they would quickly die. As long as the zero-utility income level is well below this survival threshold, the model is consistent with the fact that very poor people don’t want to die.