webgpu is a modern graphics API for modern GPUs to replace/complement these two APIs in the browser: WebGL (a very limited outdated subset of OpenGL) and Canvas (basically WinAPI drawing from 2000s)
It's heavily influenced by Metal (based on original work by Apple and Mozilla).
People are talking about it because it's on the web and it's finally something modern to work with.
TBF, WebGPU is at least a decade behind too. For instance it implements a Vulkan-style rigid render pipeline model which even Vulkan is moving away from because it turned out too rigid. So once WebGPU becomes mainstream it may very well be the most "awkward" 3D API.
It's heavily influenced by Metal (based on original work by Apple and Mozilla).
People are talking about it because it's on the web and it's finally something modern to work with.