MoltenVK is also a thing. Whatever small translation overhead it incurs is probably not that important for a text editor. And then you get a cross-platform API: not just Linux, but Windows as well. Maybe also other more niche OSes as well.
Molten VK is amazing. When I started working with it, I was expecting a lot of caveats and compromises, but it's shockingly similar to just using Vulkan that you can easily forget that there's a compatibility tool in play.
Probably you can squeeze a bit of optimization out of using Metal directly, but I think it's a more than viable approach to start with Vulkan/MoltenVK as a target, and add a Metal branch to the renderer when capacity allows (although you might never feel the need)
