I think the hardest part for any high school coach who is good is having to cook the various talent levels. Even in the public school d1 level big difference between first line and third line. Fourth line probably should be on JV. For D2 and D3 anything below the top line should probably pick another sport.
Most good HS coaches in good HS programs want their under class men skating on club teams. That’s how they develop. If your HS coach mandates JV or Frosh attendance over quality club play he is a loser. If your son is not playing for a D1 HS that is Super 8 bound then you should probably stick with your club program anyway. Don’t worry about burning a bridge as the HS coach will always take the better players in order to win games and keep his job.
coaches want/expect you to SUPPLEMENT their jv/fresh with club not replace.