What he is arguing is that scientists should learn the mindset of the arts and literature, while those in the humanities and the arts should learn the mindset of science. College courses should not be tailored in such a way that the mindset of the home department is lost, and that a course in math, let's say, has been devolved into something palatable to an arts major.
I especially like his summary at the end:
One of the few good reasons is that a mindset that embraces ambiguity is something useful for scientists to see and explore a bit. By the same token, though, the more rigorous and abstract scientific mindset is something that is equally worthy of being experienced and explored by the more literarily inclined. A world in which physics majors are more comfortable embracing divergent perspectives, and English majors are more comfortable with systematic problem solving would be a better world for everyone.
I think we need to differentiate between changing the mindset versus tailoring a course for a specific need. I've taught a physics class for mainly life science majors. The topics that we covered is almost identical to that offered to engineering/physics majors, with the exception that they do not contain any calculus. But other than that, it has the same rigor and coverage. The thing that made it specific to the group of students is that many of the examples that I used came out of biology and medicine. These were what I used to keep the students' interest, and to show them the relevance of what they were studying to their major area. But the systematic and analytical approach to the subject are still there. In fact, I consciously emphasized the technique and skills in analyzing and solving a problem, and made them as important as the material itself. In other words, this is the "mindset" that Chad Orzel was referring to that we should not lose when the subject is being taught to non-STEM majors.