Look up trasnferable objects, it's not new. The fetch api can get you ArrayBuffers that you can shuffle around zero copy, besides to webgl buffers, also to web workers.
But minimizing copying or avoiding format conversions doesn't necessarily get you best performance of course.
I had a look, that certainly looks like part of the solution, now I need to get that array buffer from my backend into the browser runtime transferable object.
I tried it out, fetching i8 arrays from a localhost server, sending to webgpu and rendering the waveform. Wow, faster than I expected, 2 billion points/sec.
But minimizing copying or avoiding format conversions doesn't necessarily get you best performance of course.