This is not completely true. The top programs seem to be recruiting slightly more HS athletes as the best available athletes are generally coming out of HS. Here are the top 10 recruiting classes and the number of commits: Texas 25, Alabama 22, Georgia 28, Ohio St. 26, Oregon 20, Auburn 25, LSU 23, Texas A&M 25, Michigan 23, Florida 25. And, the COVID year has now cycled through so you won't see players that are playing 6 years.
What is happening is that some schools are taking fewer HS recruits, like UConn, and filling the roster with proven players from FCS/G5 schools or P4 backups. So, a school like UConn may have taken a borderline FBS athlete in the past and develop them, but that is not really happening as much anymore.
If you look across the football division, there are not fewer scholarships being offered, but a player may need to go FCS initially instead of FBS.