I guess we will be saying our last goodbye to “write once, run on all major platforms” graphics code. Does this mean that the only choices now are 1. Fork your graphics code into two separate implementations or 2. Go up the stack and use a cross-platform “game” engine like Unity? I suppose 3. Stop supporting macOS is another (sad) option.
If you're programming in Rust, you can just use `gfx-rs`'s HAL[1]. This is designed to be a Vulkan-like API that works on top of Vulkan, Metal, D3D12, or OpenGL.
If you aren't in Rust, just use Vulkan. There are high-performance wrappers for it in various stages of development, such as MoltenVK[2] for macOS and iOS, and VulkanOnD3D12[3] for UWP. Non-UWP Windows, Linux, and Android should support Vulkan natively through their GPU drivers.