“Nick Bostrom, for example, despite discussing “disappointment risks”, spends quite a lot of his time thinking about very disappointing scenarios, such as AGI killing everyone, or nuclear war happening. This shows a revealed preference for, not against, receiving disappointing information.” You are presuming there is no information more ‘disappointing’ that he is consciously or unconsciously avoiding. Although those scenarios may be ‘very disappointing’ they are far from maximally ‘disappointing’.
“Nick Bostrom, for example, despite discussing “disappointment risks”, spends quite a lot of his time thinking about very disappointing scenarios, such as AGI killing everyone, or nuclear war happening. This shows a revealed preference for, not against, receiving disappointing information.” You are presuming there is no information more ‘disappointing’ that he is consciously or unconsciously avoiding. Although those scenarios may be ‘very disappointing’ they are far from maximally ‘disappointing’.