I have trouble with concept of WGPU. GPUs are complex by themselves to bolt on top any abstraction that is coming from Web. But its just me, its not important since I am not a 3d programmer myself. I am more Engine / CPU optimization guy.
My interest in Rust and this topic is that i would like to see fine grained task parallel systems written in Rust. Instead of systems with separate thread for render that became a bottleneck years ago. I wish you good luck and hope to see a success story about Rust.
WGPU's API is basically Vulkan. It exists mostly to deal with Apple's Metal. Metal has roughly the same feature set as Vulkan, but Apple just had to Think Different and be incompatible. I'm not supporting the Wasm or Android targets. Android and browsers have a different threading model, and I don't want to deal with that at this stage. Linux/Windows/Mac is enough for now.
Thought for the near future - will VR and AR headgear have threads or something more like the processes with some shared shared memory model from Javascript land?
(That video isn't me, it's the Rend3 dev, who also works on WGPU.)
I dont work with VR/AR myself so I dont know.
The Rust game dev ecosystem is far enough along for simple games, but not there yet when you need all the performance of which the hardware is capable.
[1] https://www.youtube.com/watch?v=DDG4bcGs7zM