> shocked if more than 0.1%
MIT has ~1000 non-emeritus professors. So order 0.1% would permit 3 cases. But that's including biology, and non-science/non-engineering, which I didn't include. So it's at least low order 1%. And I'd be unsurprised if it's at least several percent. And not shocked by ten.
Consider an old professor. They may well have not had a biology class in high-school or college, let alone graduate school. And never touched biology professionally. And either not have had kids, or was not deeply involved in their science education. So we're down to "ambient general knowledge". What percent of the general population of PhD's with only ambient exposure, have any idea what DNA is? And many professors are among the busiest people I know. Imagine asking a serial startup CEO, what do you mean you don't know who entertainer-X is, aren't you watching TV and following popular culture? Well, no. So no need for shocked?
Very rarely, a professor giving a talk, will put the audience on the spot. A room of EE/CS professors may not recognize astronomical tidal forces. Half a room of MechE profs may think red blood cells are thinly scattered in blood.
Sure, common curiosity trims the numbers. But it's not universal. A now-retired physics professor might respond to a suggestion that they use biological examples in their intro physics problems, with "WHAT! You want me to teach... biology?!?!?!".
At the other extreme, there are a few impressive polymaths. But even there, out of field, competence is uneven and has holes. Impressive, impressive, WTF basic misconception, impressive... Similar to comments that when Hans Rosling started doing immigration, he tripped on some basic misconceptions.
Out of field, one isn't "embedded in a critical community". Part of how science works, is people being very afraid of being embarrassed by getting it wrong in front of their peers, and so putting in the effort and questioning to avoid that. Out of field, no one cares. One still has some habits of thought, but the edge isn't there.
And baseline unmotivated competence is not high. There's an old video[1] made out of Harvard, which includes graduating MIT and Harvard students, given a battery, one long wire, and a small lightbulb, and asked to make light. And failing, and failing, and...
[1] https://www.learner.org/resources/series26.html
Re "PS: I loved the second link!", thanks! :)