So first year students can live on campus in the fall semester but not attend classes in person. I understand all classes having an online option, but am surpr

So first year students can live on campus in the fall semester but not attend classes in person. I understand all classes having an online option, but am surprised they aren't mixed modality so the students on campus can be in person. Is it more difficult/expensive to make a classroom safe than the rest of the campus? Or professors have pushed back on mixed modality (due to health and/or logistics concerns)? Or something else?