OpenGL will not be on the way out until Khronos defines an high level alternative to Vulkan, as not everyone enjoys being a GPU driver writer for doing graphics.
Dawn and wgpu are also collaborating on a common set of native headers (https://github.com/webgpu-native/webgpu-headers) to make it easy to switch between implementations.
Regardless it's the closest portable solution at the moment, and it will continue to add capabilities. The WebGPU CG has already had public meetings with Khronos to talk about running WebGPU on top of Vulkan, and running Vulkan Portability on top of WebGPU. So I think there's a lot of interest in making WebGPU succeed on both web and native targets.
If WebGPU ends up being as castrated as WebGL, then we either keep using OpenGL, or change to modern middleware engines (which is what most are doing), with the added benefit that they make the actual 3D API less relevant, it is just a checkbox.