Listening to this sounds like there was a lean towards smoothness over track ability, and I would guess the feedback on DCT for DD was more of an influence than the track crowd.
I would also venture that putting in a DCT in the G80 would have been another powertrain permutation and higher cost than using the same platform as the m5.
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2023 F90 M5
Retired - 2021 G82, 2019 440xi, 2020 X7, 2019 X5, 2013 F10, 2010 F10