You may still have some industries, but sales taxes and property taxes will take a massive dip. Add that to drops in every retail and service industry. Nearly every restaurant, hair place, clothing store, grocery store, hotel, and other retailer depends on students being on campus to break even. Large portions of that are directly dependent on football games themselves (think restaurants, clothing, hotels, and other retail-even gas stations). Manufacturing and agriculture may largely stay in tact, but that's about it.
Students probably keep the fast foods going and don't always do a good job at that, since they couldn't keep Zaxby's open even though it wasn't located very far from campus. Older folks largely help keep the restaurants going, such as Texas Roadhouse, Freddie Paul's and Mexico Joe's. The same with most other businesses not primarily geared toward college students. Really, students only have so much money left to spend after paying the landlord and bills. It's really landlords that would be most hard hit by fewer students. One apartment developer planning to build near Eskimo Joe's pulled out after seeing declining enrollment numbers at OSU. I'm sure many landlords were relieved by that.
Until covid, old folks also kept the shows and concerts packed at the McKnight Center. Students avoided them like the plague. Hopefully, OSU won't have layoffs from fewer students.