Why would having "gifted" classes detract from other students? In the case of OP's daughter giving her permission to simply skip math class and self-tutor in an empty classroom (by e.g. self-studying a more advanced textbook) would probably be an improvement over having to sit through a class that's below her level.
Once you do that less "privileged" students also benefit, since the teaching resources being spent on that bored student will be freed up to focus on the smaller class of students that need more assistance.
I don't see why it's a given that this is guaranteed to result in worse outcomes by any measure, even "woke" ones that might consider it a loss if OP's daughter pulls ahead further from the median grade, even if the median also goes up as a result of better spent teaching resources.
Once you do that less "privileged" students also benefit, since the teaching resources being spent on that bored student will be freed up to focus on the smaller class of students that need more assistance.
I don't see why it's a given that this is guaranteed to result in worse outcomes by any measure, even "woke" ones that might consider it a loss if OP's daughter pulls ahead further from the median grade, even if the median also goes up as a result of better spent teaching resources.