I’d take such reports with a grain of salt. It addition to Chicago undergrad kids almost certainly averaging far higher LSAT stats than average, it’s easy for a college that likes to brag about a high rate of professional school acceptances to manipulate such stats. For example, a school might discourages students from applying to professional schools where they are likely to be rejected, or encourage students to apply to bottom of T15 over what may be better options.
If you look at individual pre-law students at Chicago, many have far from positive things to say about their experience and law school admissions results, which some associate with harsh grading at Chicago. An example thread is at Honors graduate with 174 LSAT shut out at top law schools . He had a 3.3 GPA + 174 LSAT. He claims he was “shut out at top law schools” due to his lower Chicago GPA (at the time near Chicago average), but was accepted to the bottom of T15.