Many on this board will tell you to have your son settle things with the coach and adjust his attitude. The only one who can make this call is your family. Nobody on this board knows your son or his coach. Most are assuming your son is wrong (he may be?) but we don't know for sure.
A very good player came to my sons high school team last year because he could not along with his old coach. Our team did very, very well and the so called "trouble maker" has since committed to a D1 program in So Cal. He was a good kid and teammate according to my son. You just never know.
Good luck, a new school/head coach may be just what he needs.