Baseball has definitely seen a resurgence in Iowa, at least in Central Iowa. Anecdotally what seems to really drag overall participation numbers down vs football is attrition. A lot of the large schools have a huge number of 8th graders and Fr out for baseball, but those classes thin out a lot by the time they are Srs.
My observation has been that in football if a guy sticks with it and works hard in the weight room and other training sessions there’s probably a role for him as a Sr. In baseball there are lots of guys that are behind people in their grade or below on the depth chart and see the writing g on the wall. Plus baseball at the varsity level is pretty all consuming of your time May - mid-July, so it’s tough to work or do much else. Football is a big commitment, but it’s a little more spread out and less intrusive in the summer.
I think at Ames we have had 30 plus freshmen, only to have senior classes in the single digits in baseball. In football there might also be 30 ish Fr but 20-25 stay out for four years.