If you really want to be specific, except for Xavier they were all 4A teams last year.
All the players (except freshmen, of course) on Lewis Central/Western Dubuque/North Scott have experience playing a 4A schedule. Xavier hasn’t been 4A since 2013 - this year’s seniors were in 7th grade the last time Xavier played in 4A.
Although I think the harping on this fact is silly. The state defines how the classes are defined. The schools play within the guidelines of what the state sets up. The schools don’t control what size schools go into what classes, nor really, even what enrollment they have themselves. You play the schedule you’re given. Can reasonable people disagree on how the state sets things up, and can they present different ideas for making it better? Absolutely. But this is the way it is, at least until the end of next season.
(I also think it’s kind of funny when people say Xavier, for example, dropped to 3A so they could collect championship trophies. You realize it took them 4 years to get even one championship, right? And they don’t appear to be the favorites this season. I don’t recall anyone saying Pella needed to volunteer to play up in 4A when they were going back-to-back-to-back ...)