That depends, people can be smart but malicious, non-coorperative, or selfish.
The prisoner’s dilemma shows that there are systems where individually, the “smart” individual thing to do is globally non-optimal.
Even smartness and altruism alone isn’t enough. Medical professionals are smart and out to help others, but any ER doc/nurse will tell you they have limited trust in their patients (rightly so in the real world).
Does “everyone is smart” also include both “altruism and cooperative trust in others”?
Bad abstraction is worse than no abstraction
If the code is going to poorly organized, I’d prefer it to just be one single gigantic standalone script than some wrong and misleading arrangement of objects or functions that adds more complexity than they solve