Most likely minor behaviour differences or bugs in specific Linux Vulkan drivers or driver versions and the Chrome WebGPU team first wanting to get other platfo

Most likely minor behaviour differences or bugs in specific Linux Vulkan drivers or driver versions and the Chrome WebGPU team first wanting to get other platforms in shape. Chrome for Android has WebGPU enabled and that also runs on top of Vulkan, but I guess Google has more control over driver quality in the Android ecosystem than on Linux.