What Goosegg posted is true and good advice.
One thing I'll add, though: a super competitive HS baseball program can have the following very beneficial effects: (1) the coaching can be excellent; (2) the competition to get on the field can be intense, causing the players to drive each other to excel beyond what they would otherwise achieve, and to learn to "work while you wait"; (3) the competition they play against can be excellent -- many states have classifications that pit the top programs against each other, plus there are national tournaments -- which can really help in the development of the player (you get better by playing against better competition); and (4) the last item can help in recruiting -- if your son's HS video clips are of him facing D1 commits or MLB draft picks, it doesn't hurt, that's for sure.