I’m not sure if this changes things, but the probabilities of the OP were reversed:
If there was a button that would kill me with a 60% probability and transport me into a utopia for billions of years with a 15% probability, I would feel very scared to press that button, despite the fact that the expected value would be extremely positive compared to living a normal life.
I’m not sure if this changes things, but the probabilities of the OP were reversed:
Ah ha ha, then my utility function is likely very different from the OP’s!