I think in the case of governments the most important thing to prevent is abuse of power to 1. increase ones own power against the spirit of the constitution and 2. to gain personal advantages at the cost of the ideal management of society. Being a good forecaster guarantees none of those things. Incompetence is usually preferable to malice in government. Maybe a forecastocracy is a good form of governance in domains where all participants goals are aligned (for example when humanity tries to prevent a meteorite hit).
I think in the case of governments the most important thing to prevent is abuse of power to 1. increase ones own power against the spirit of the constitution and 2. to gain personal advantages at the cost of the ideal management of society. Being a good forecaster guarantees none of those things. Incompetence is usually preferable to malice in government. Maybe a forecastocracy is a good form of governance in domains where all participants goals are aligned (for example when humanity tries to prevent a meteorite hit).