See my answer to artemonster above.

WegGPU is a way nicer HAL if you're not an experienced graphics engineer. So even if you only target desktops, it's a valid choice.

On the web, WebGPU is only supported by Chrome-based browser engines at this point, and a lot of software developers us Firefox (and don't really like encouraging a browser monoculture), so it doesn't make a ton of sense to target browser based WebGPU for some people at this point.

It's not as much about experience as it is about trade-offs. I've worked a lot with Vulkan and it's an incredible API, but when you're working alone and you don't have the goal of squeezing 250% performance out of your GPU on dozens of different GPU architectures, your performance becomes pretty much independent of a specific graphics API (unless your API doesn't support some stuff like multi-draw-indirect, etc).

The answer is middleware engine, all of them with much nicer tooling available, without the constraints of a browser sandboxing design, for 2017 graphics APIs minimum common denominator.