> that's less than 10% of profs at big name research-driven schools
From my experience that extends quite a bit further than that too even for a university that wasn't research heavy. I'd argue about half of my lecturers at university back in the day saw Level 1 classes not only as a hassle, but had active disdain for teaching them.
Which is totally backwards, as these classes are the point of contact where energetic, motivated new students get that magical passion that pushes them into an entire life in the field. When I was in grad school and expressed a desire to focus on teaching, primarily 100 & 200 level courses my supervisor said "that's the punishment we reserve for those who are failing in their research". Totally crushed my desire to work at converting tangential students into future leaders in our field.
From my experience that extends quite a bit further than that too even for a university that wasn't research heavy. I'd argue about half of my lecturers at university back in the day saw Level 1 classes not only as a hassle, but had active disdain for teaching them.