Amen.
The athletes had a choice: work with their school's coach, or not. They chose to not work with the school's coach, because they think their situation is improved by working with someone else. That's fine, that's their call - it's unfortunate for the program that they couldn't work with their HS coach, but it is what it is, and that is a decision they had every right to make.
Likewise, the coach should never allow a group of uncoachable athletes to run for the program - either the athletes are working with their coach to build the program up, or they should go their own ways and do their own thing and let the HS coach build the HS program. As a coach, you cannot allow a small group - no matter how talented - to unilaterally dictate your program's direction (e.g. whether you should allow an private coach to influence the program from outside, up to and including not working out with the team).
To others on this thread:
There is no need to rail against the Brentwood coach - he did what he should have done in that situation, which is provide structure and order and build the program with ALL of the current and future athletes in mind. Any posts trashing what that coach did on the basis of how the boys team didn't match what the previous group matched is just ludicrous: maturity and talent plays a HUGE role in how good a team can be, and it should come as no surprise that when an upperclassmen group that just qualified for NXN the past year quit the team, the team won't have similar immediate success with mostly freshmen and sophomores that haven't broken 17 for 5k before.
If the Brentwood kids going to NXR prefer to work with their private coach, that's great (for them). But they do that realizing that they are forfeiting their right to compete for their high school. That seems to be something they are fine with, so I don't know why folks on this board who aren't a part of the situation would bother complaining about it. Hopefully, the next group of talented kids at Brentwood decide that they can work with their school's coach and not have to have this situation.
As a side note, it looks like Brentwood has a combined boys and girls program, and the girls seemed to run well for the new coach (fifth at state). Seems like a promising start, beyond this drama of the talented group of boys.