I don't believe native DSD is supported on OSX at all, only DoP.
DoP is still true 1-bit DSD though, it is not converted to PCM.
DoP simply transmits DSD inside a PCM container.
Rather than being a 1-bit 2.8MHz signal, it is put into a 16-bit 176.4kHz PCM container. 2.8MHz ÷ 16 = 176.4kHz.
Inside the DAC, this is reconstructed back into a native 1-bit 2.8MHz signal.