What kind of program are you building when you just throw the guys under the bus that have invested four years in your program? What does that tell those underclassman? Maybe when I am a Sr the coach will just throw me under the bus?
Just play the best players. Play the guys that give you the best chance to win that day. Give everyone an opportunity every chance you get to get experience and get the experience of playing. Those same people crying about the underclass guys not getting opportunities will be the same ones crying about their player losing playing time to a younger player later in their career.
The coach has a team and a program to be concerned about. Some parents are only concerned about their kid and what he is getting or not getting. For goodness sake sit back and enjoy these years and stay out of the politics and complaining. Let your son make his mark and earn what he gets. You will enjoy these four years much more. And so will he. JMHO