Luke Cage was a Netflix Original. Netflix often locks audio tracks to specific regions. A "Dual" release typically merges the English 5.1 track with a dubbed track (usually AAC 2.0).
Keeping a show about a in 720p is a quiet metaphor: Luke Cage.T1.720p x264-x265.Dual
x265 version offers smaller file sizes without sacrificing 720p visual quality. Luke Cage was a Netflix Original