I think native DSD playback internally would be too difficult to bother, but it should be possible to at least support DoP output as a USB transport.
It's just a matter of firmware being able to push the DIFF/DSF into DoP packets. No intense transcoding is needed.
Both AK (via USB) and FIio X5 2nd (S/PDIF) was able to achieve DoP via firmware update at a later stage, so I would find it surprising if Shanling cannot do this, given that the firmware development company is the same as Fiio.
In the meantime, it's great that M1 can output PCM 352.8 kHz