I realize that was the reported experience of one student you know, but that is not consistent with Carleton’s reputation nor the experience of Carleton students I have known over the years. While Carleton is like most SLAC schools that tend to have student bodies with a more liberal tilt on some issues, Carleton students are typically friendly and open-minded.
The purportedly right-leaning FIRE organization that ranks colleges on how open each campus is to free speech and differing views ranks Carleton as only slightly below average and higher than Bates, on a list that has Harvard on the bottom. That whole list has dubious value, but reflects Carleton’s reputation generally.
Carleton also retains a bit of a midwestern sensibility despite attracting students from all over.