Hi Andrew,
MQA can be decoded by a DAC, but The Absolute Sound article with Bob Stuart said the decoder can be implemented in many ways, including as a bit of software. In that case I expect the resulting 192KHz PCM stream can be sent to a non-MQA DAC. Both Tidal and Roon intend to implement MQA decoding in software.
It seems to be a live issue for debate whether an MQA DAC will have some advantage over a software decoder. Time will tell.