Modeling (and possibly economics, especially) is rife with simplifying assumptions that break down in practice. You can find many economists who think modeling individuals as rational agents is a "fine and widely used assumption" while also finding many economists and psychologists showing where this assumption can get you into trouble. There is a big difference between "this assumption is made because it reflects reality" and "this assumption is made because it makes my life as an economic modeler not suck." The latter is still fine, but only if you're upfront about its limitations.
Modeling (and possibly economics, especially) is rife with simplifying assumptions that break down in practice. You can find many economists who think modeling individuals as rational agents is a "fine and widely used assumption" while also finding many economists and psychologists showing where this assumption can get you into trouble. There is a big difference between "this assumption is made because it reflects reality" and "this assumption is made because it makes my life as an economic modeler not suck." The latter is still fine, but only if you're upfront about its limitations.