Basically every software (except Logic) is available on Windows but users still buy Macs. Even among those users, people usually fallback to ASIO instead of directsound or wasapi backends.
WASAPI requires exclusive mode to be useable for pro applications, or else your latency will suffer and they may be doing some resampling behind the scenes.
Exclusive mode is a feature, not a bug. If the user needs the bits coming out of the user's DAW to reach the speakers as pristine as possible, then the user probably doesn't want these bits mixed with any other application. If the user needs to switch between the DAW and a Youtube tutorial, then there's probably no need for exclusive mode.
Latency is a valid concern, but is it really bad? PCs are fast now.
afaik it's not possible to configure buffer size and sample rate from within a user application without exclusive mode, which actually does matter for the non-exclusive use case. iirc it was even worse where applications' streams would be resampled transparently and buffered, which is absolutely not what you want.
I don't use windows for audio anymore so I can't comment on this in win11, but it used to be that WASAPI suffered unless you set your PC in "performance" mode in your power settings whereas ASIO was unaffected.
And yes, latency matters! For live performance you're looking for < 2.5ms of one-way latency to get a roundtrip of under 5ms. After that point it starts being perceptible to players. This is not a performance floor so much as a scheduling one, and ime windows audio scheduling under dsound/wasapi was always shakey.
For a DAW running in exclusive mode, wouldn't they also have the option of setting the system default output to a virtual device that inputs into the DAW? That seems to me like it would be the most sensible way to handle mixing in YouTube or whatever.
