It may be an error in the sample code, but it doesn't seem to be. The Capture Preview sample app shows HDR static metadata, but the Rec.2020 primaries displayed here are in GBR order, but labelled as RGB:
HLG_metadata.png (198.73 KiB) Viewed 1222 times
Rec2020_primaries.png (100.01 KiB) Viewed 1222 times
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