sorry, what?
n-tit-for-tat behavior is the family of game-theoretic strategies where you respond to a defection by defecting one or more times, but if the other participants don't defect then neither do you. Most societies encode this kind of behavior as some system of honor and propriety, where you don't transgress against another person unless they transgress against you, and then you are free to engage in various degrees of retaliation.
tit-for-tat would be proportional response, and then you have a whole continuum of disproportionate response up to grim trigger (infinity-tit-for-tat), which would correspond to a blood feud or something.
ntft strategies are known to be highly performant or even optimal in many settings, and are very easy to compute.
As testosterone levels decrease, the viable societal distribution of n goes down, at some point drifting into sub-1, which pushes you into a sub-optimal strategy domain.
One obvious source of this problem is that n-tit-for-tat behavior in humans is moderated by testosterone levels, which have been declining precipitously. 100 years ago you had personal vendettas between CEOs driving corporate policy, which is unironically good for society because it encourages real non-kayfabeized competition and the punishment of antisocial corporate behavior.