I don't think that's accurate. Creating a shading language is obviously a huge effort, but there were already years of effort put into WebGPU as well as implementations/games building on top of the work-in-progress specification before the shading language decision was made (implementations at the time accepted SPIR-V).
The PoC was made in 2016, the work started in 2017, but the first spec draft was released on 18 May 2021. [1] This first draft already contained references to WGSL. There is no reference to SPIR-V.
Why did it take this long to release the first draft? Compare it to SDL_GPU timeline, start to finish in 6 months. Well, because the yak shaving on WGSL had already begun, and was eating up all the time.
Sure, but that proves my point. They took so long to decide upon the shading language that implementations had to erect a separate scaffolding just to be able to test things out.
Scaffolding wasn’t a problem at all. Both used SPIRV-Cross for shader conversions at the time and focused on implementing the rest of the API. The shading language barely matters to the rest of the implementation. You can still use SPIR-V with wgpu on its Vulkan backend today for example.
