Sorry to disturb you with the simple facts concerning color gamuts in video standards. But there is no ATSC color gamut standard. NTSC has a very broad gamut, but NTSC is dead. Pointer's gamut is probably adequate for practical use. But ATSC doesn't care. It expect the primaries and white point to be specified in the stream; it's doesn't define them as a standard.
You are obviously way too smart to understand that. Primary colors. White point. Pretty simple stuff.
HFCUIS. LKF. FCK,WAFA. AASBDF. OK, li'l buddy?