I don’t believe the question is actually answered! Just a list of heretical views and why they may be considered heretical. Fascinating article.
TFA seems to use the term to mean "mainstream" or "popular"?
I'm sure it doesn't mean "sanctioned by the Catholic Church", which is the meaning I had associated with that term before thinking about it.
That lowers the bar considerably, plus it opens it up to things that are merely unlikely: Man Utd will win the premier league this year, world war 3 will break out in Ukraine, Trump will be restored.
I'm tempted to be snarky and try to tie Cowen's "economics curmudgeon" reputation into this and say that Cowen is just trying to toot his own horn, like the "Intellectual Dark Web" folks did, but that's uncharitable.
How about "heresy is a canon law thing and doesn't make sense outside of some rigid system of religious authority" as a take? I mean, Triclavianism is (maybe) a Catholic heresy, but virtually all the world's population would either shrug it off, or laugh. Of course Triclavianism is in Cowen's #3, Not globally heretical.