I don't believe there is more to it than the researchers getting exploration/exploitation wrong in this case. Say somebody wants to get funding to fight AIDS,

I don't believe there is more to it than the researchers getting exploration/exploitation wrong in this case. Say somebody wants to get funding to fight AIDS, based on the hypothesis that it is caused by something else than a virus. The research community would oppose funding this and they would be right. At some point you have to reject some hypotheses, there's just not enough time and researchers to keep researching every not-so-promising hypothesis. Sometimes the research community will get that wrong but this is the cost of having research focused on the most promising hypotheses.