Well, TOSU being down 4% is kind of amazing. If they are down then the MAC schools should expect to be down even more.
I don't think there is a direct correlation. It depends on the reason. If the reason is increasing ambivalence towards football, as Recovering Journalist suggests, the MAC may be hit harder than OSU. If it is due to TV, as the Dispatch suggests, it could go either way, but OSU might be down more. If it's due to price, as buckeye to bobcat suggests, the effect could go the other way, as fans opt for the lower ticket prices in the MAC.
I suspect it's some of all the above reasons.