This is a helpful perspective. He will absolutely apply to a couple of less selective BM programs, as it seems (now) that he really wants most of his classes to be music classes. A BM does seem like the best fit for him at this moment, and we are excited for him to do it.
But he is going really hard right now, and part of this as a parent is also helping him hedge against music burnout before his senior year is over. Maybe he gets tired of the grind before then, and decides he wants to play music on the side but not as his main thing. It seems unlikely now, but weirder things have happened, and kids are always changing.