The Nintendo Switch has an ARM64 CPU, which means the biggest part of porting to that CPU is now done. Does it mean we can expect an Apple Silicon mac build some time soon(ish)?
No. It’s a completely different graphic stack.
If you target PC/Console and don't have an abstract GPU interface, then you should rethink your life choices
And all the graphics stacks nowadays are similar, Vulkan, Metal, DX12, all share the same ideas
Also there are countless opensource cross platform GPU libs, bgfx [1] or sokol [2] for example