Yeah it's a pet peev of mine as well. People define very tight space and then proclaim actions irrational if they don't make rational sense in that setting.

Which wouldn't be a problem in itself if there was discussion about the defined space and if it is an actually good model.

A big chunk of economics is like that, if the data doesnt fit the model then too bad for the data. Same goes for metrics used, externalities are like a side note in economy books and not an example of fundamental issues with current economic toola and modeling.

And it's not limited to introductory level either. Nordhaus had most asinine assumptions in his model and he got the pseudo-Nobel.

It's not pretty.