The overall popularity of football ( not participation) seems quite high. High schools will need to play football with other schools at the small school level. Numbers at larger schools seem ok?
Numbers even at larger programs seem to be falling off for a variety of reasons.
More options for kids to form bonds/community other ways than sports
Pay to play
And the thing many I've talked with are seeing is flat "Burn out" for a lot of kids.
Why do MAC schools constantly have 70+ kid teams in similar communities to a covington etc? Many I've talked with point to their lack of youth football. Some communities youth football starts early summer, even before HS practices and goes later than hs programs, while playing on the varsity field and in some cases having much nicer equipment.
Why play HS when you have a super bowl ring from little league? Or all you did was run at each other in practice to see who could knock the other over. Loser has to run. Or you got hurt. I know some friends who's kids play 12-15 games in youth football, including a tournament (in 1 weekend like baseball). Things that until deep playoff runs/college that do not take place anywhere but youth.
While your D1 and 2 schools will feel the impact slower. They are feeling it. 500 boys in a graduating class and only 15 play football? That is not a good percentage. Now put that percentage on a school with 100 boys per class (that would be 3 per class). Small schools are going to feel the crunch much faster.