the thing about the use of multi-ch DAC in consumer market is, multi-ch DAC does not contain any audio codec to decode Dolby/DTS/Auro3D signal.
And since SACD is not available on PC, nor as bit-stream for external processors, multi-ch DAC has very limited use in LPCM, file-based DSD/DXD.
This market is already saturated by interfaces, that is harder to use, requires routing, relies on even more advanced connection and engineering such as AoIP and thus will not work out of the box.
Multi-ch DAC will not be a thing as long as codecs remain closed and proprietary. MPEG-H could be a game-changer though.
You don't need a codec in the DAC because you decode in software on the machine.
The last time I checked, Dolby TrueHD and DTS-HD MA were playable in their full lossless formats upto 7.1ch.
Atmos and DTS:X have their 7.1ch lossless core playable, but no object audio (yet... there is a bit of interest and development work going on for that end of the format).
Auro3D from what I read is just extra metadata embedded in an LPCM 7.1 stream, so that would be the hardest one to get going, but not impossible given that a true Auro3D setup is still just DSP-based afaik.
There is a worry about patents in the US (until about 2035 for Dolby TrueHD/DTS-HD MA, 2039-2040 for Atmos/DTS:X, anyways), but for most countries that's not an issue since there are no software patents (nor have I heard of any USA-based individual user getting sued for codec-related patent infrigement).
SACD isn't a problem either - as Kal already mentioned, it can be ripped, and personally I would always convert to PCM during playback because the convenience of having shared mode playback for things like having music while playing games or chatting with friends on Discord far outweighs the sound quality improvment of exclusive or non-PCM modes.
As for MPEG-H... MPEG-H feel like a play for putting proprietary file formats when
open Ambisonic file formats already exist.