It actually can.... if Illinois had an "open class" that you petition into in some type of yearly increments. IMHO5A game is at 10:00am and 6A is at 1pm. If you had a choice, which game would you want to play in?
On a more serious note, Mascoutah is in 5A and has a real chance. After ESL and BW won basketball in 19, the area would like to spread out the representation over as many classes as possible. The best team in the state is strictly someone's opinion and can never be proven.