Minority advocates don't always approve redistricting that gets them "one of their own" as congressman. Because then your political power is concentrated into one voice in Congress; perhaps your interests may be better served diluting it out over a greater number of districts, generating sizeable voting blocs for multiple congressman to have to take account of -- it might be a road to more influence than simply having one massively minority district (and a minority representative) among many massively white districts (with congresscritters not beholden to minority interests).

But NC, of course, has a serious "bad intent" problem that has affected most of the legislative activity around electoral matters for a while. These districts were designed to reduce minority voting power by channeling all their votes into a single seat, leaving scores of other seats created in "safe" white/right-wing districts