I have not heard a single argument why DAW software can not have a web GUI. Do you have any? I'm genuinely curious.

There have been various toy DAWs the have web GUIs. I've never seen a production-capable DAW with a web GUI.

I suspect that existing web-as-native-GUI frameworks make presumptions about threading that won't work where a realtime audio callback thread piping data to other audio processing threads and back is the real show, and where the GUI may need things like updated zoom levels dirtying many waveform drawings at once requiring recalculation of peak values in viewable windows to draw the little lines that make the waveform, among other things that may make simple partitioning of systems more challenging...