One glaring presupposition (which is false) of "rationalist approaches", but also those who reject them, yet maintain the same inherently hyper-individualistic, atomistic conception of human beings[0], is immediately apparent in the first sentence of the abstract: "Rationalist approaches to economics assume that people value their own interests over the interests of strangers."

It is NOT in my interest to be dishonest. To think it is is to fail to understand that human nature is thoroughly social and that, because of that, there is a common good. The common good is prior to private good; the latter depends on the former, not the other way around, as liberal philosophy conceives it.

Thus, maximizing my own interest, by which I mean my own good, is to live maximally in conformity with human nature, and part of that means living in a way that recognizes the primacy of the common good. Dishonesty per se is also harmful to the individual in the very act of being dishonest. A person is corrupted in the very act of being dishonest.

[0] I am not denying the existence or worth of individuals. I reject collectivism which is ready to throw the individual under the bus for the collective (which is rather incoherent). I mean only the conception of human beings as atomic, in which society is merely transactional or contractual, instead od recognizing transactions as a subset of actions that occur within a social context and only where transactions are appropriate and make sense).