I think there is a useful distinction to be made between fields like physics, where expertise in the field makes you more likely to make accurate predictions (e

I think there is a useful distinction to be made between fields like physics, where expertise in the field makes you more likely to make accurate predictions (e.g. about when that comet is going to appear in the sky), and fields like economics, where expertise in the field actually makes you less likely to make accurate predictions than a non-expert (e.g. whether we will have a recession soon). Consider an expert in medicine, back when the "four humours" theory of medicine was what experts used. A non-expert would think, "bleeding is bad, I don't want to bleed, I need my blood". Experts believed in bleeding their patients/victims to restore a balance of the humours. George Washington was probably killed by his doctor in this way. Being an expert in a field only helps, when the basic theoretical models of that field have reached a certain minimum level of maturity.