Actually it might be, Zink just got OpenGL 3.0 support.

Zink is an OpenGL Implementation on top of Vulkan and that might actually be a good way to do full OpenGL on these devices.

Zink has next to no optimization effort so far and is thus very slow from what I've read. Maybe in a few years, since they currently seem to be focusing on compatibility.

Which is the right way to go about it, especially when Vulkan is still in the process of being adopted. Make it right; then make it fast.

But it's only a small subset of Vulkan that this driver implements. I would be surprised if it's enough for an OpenGL implementation.