Either way there's no basis to dismiss people's opinion solely on their primary field of study. One obvious example would be Noam Chomsky. He's deeply knowledgeable outside of his primary field of linguistics.
> very economics research department on the face of Earth has a cohort of "heterodox" economists,
The most common use of heterodox seem to span from status-quo to far-right libertarianism. That's not very imaginative.
> I'm just saying, it does get a bit ridiculous when American socialists start telling me and other people from my country what we're supposed to think and feel.
I'm Swedish, but I assume that wont change anything there. Being from a country doesn't necessarily say anything, you may be from a privileged class of that particular country and thus have that view of that country.
> You might have a point when you talk about economists in think tanks and hedge funds and whatnot, but those guys aren't usually the ones producing most academic material.
There is no other field of study as obviously connected to money and power than the field of economics. This makes it totally reasonable to be skeptical of what comes out of that field.