It's less concrete and actionable than you'd think, because measuring (and therefore identifying and internalizing) externalities requires utility assessments, and experienced utility is subjective and immeasurable and it's very, very easy for ones preferred outcome to influence one’s choice of utility estimator. (And even easier for it to lead you to find an excuse to dismiss someone else’s.)

> and not something I think anybody really disagrees with on paper.

I think the general opinion of both the Chicago and Austrian schools is that efforts to internalize externalities are generally a bad idea, and in the Austrian case specifically wrong on principal.

Public figures adhering to those viewpoints are likely to couch them in circumlocution outside of addresses to selected audiences because they are very large groups with which they are dealbreaker positions, but they aren't exactly obscure positions.