I think part of the appeal of 93XRT over the years has been to feature bands & artists that simply don't get much airplay on a more traditional rock station. 93.1 FM tries to balance the free form, alternative rock with classic rock from more established bands & artists. To this day, WXRT also still has a very strong brand which has resisted format changes elsewhere on the radio dial.

I also think it's been this way even before Westinghouse/CBS Radio, now known as Audacy, acquired WXRT and 670 AM The SCORE from Diamond Broadcasting in 1995 for $44 million.