[kvark]

Metal also is quite different between mobile and desktop, so it's not solving this portability issue completely. It has the benefit of standardizing more of the limits/capabilities in the feature tables as a part of the "spec". This is much better than querying everything about the physical device at run/init time and making decisions from there.

Where Metal is really different, in a good way, is that it has progressive complexity. You can use the basic commands and get pretty far, allowing the driver to manage lifetimes for you and not caring about multi-threading too hard. But then there are ways to get more control, gradually, which you can opt into later. This is very different from Vulkan's all-or-nothing approach.

For the Web, it seems to me that having the same property would work best.