I suggest the essential difference is whether the link is 'feed-forward' only, like S/PDIF, or if it is bi-directional 'on-demand' like asynchronous USB i.e. the DAC requests packets of data.
In the former case, the DAC has to synchronise to the incoming stream, which means it has to adjust its own timing occasionally, or re-sample the data. This will be affected by jitter and the quality of the link at some level, even if the bits always make it through intact.
In the latter case (by the power of Thought Experiment) the physical implementation doesn't matter as long as the bits make it through intact and in time. USB, ethernet, fibre optics, WiFi are all equivalent.
TIDAL works, and nobody can say exactly what path and what types of link have been used to get to your house - indeed it changes all the time - which (by the power of Thought Experiment) suggests that it is possible to make a receiver completely independent of the physical implementation of the link. If the claim is that only the final element in the chain matters to the sound, then (by the power of Thought Experiment) make sure that your favourite type of link is actually built into the DAC itself, with a universal converter interface in front of that, and then you can be confident that whatever you connect to it cannot affect the sound.
In the former case, the DAC has to synchronise to the incoming stream, which means it has to adjust its own timing occasionally, or re-sample the data. This will be affected by jitter and the quality of the link at some level, even if the bits always make it through intact.
In the latter case (by the power of Thought Experiment) the physical implementation doesn't matter as long as the bits make it through intact and in time. USB, ethernet, fibre optics, WiFi are all equivalent.
TIDAL works, and nobody can say exactly what path and what types of link have been used to get to your house - indeed it changes all the time - which (by the power of Thought Experiment) suggests that it is possible to make a receiver completely independent of the physical implementation of the link. If the claim is that only the final element in the chain matters to the sound, then (by the power of Thought Experiment) make sure that your favourite type of link is actually built into the DAC itself, with a universal converter interface in front of that, and then you can be confident that whatever you connect to it cannot affect the sound.