[MiracleUser]

Necessary to what end? It could be necessary to maximize survival for the species, but that doesnt make it necessary to maximize survival for an individual.

It's perfectly possible our heuristics are muddied beyond necessity in order to generate variety in action, so as to reduce risk to the unknown for the species - even though it would cause a minority of individuals to consistently make sub-optimal choices. From a speculative standpoint, it's easy to find examples of people doing things that we consider 'stupid' but it pays off because of some unlikely event occurring in coincidence.

Reality has a lot of unknowns. There is no perfect model that could account for that. It's possible being hyper-intelligent (beyond our current ability) is (or was) a disadvantage for the species

[orestarod]

Take depression and nihilism for example. Great intelligence can overcome the very drives that makes us want to keep living - which is an arbitrary cause, and an extremely tedious activity.