you dont need to truly understand the complexities of the math to use them to draw models and stuff (god knows i dont, i just know the bare minimum, and i can get by)
Arguably vulkan could widen device support and unlock many cool technologies / features, but practically they likely have a huge number of existing DX focused & optimized content, which would largely go to waste
vzerouppervzeroupper is used for basically any floating-point code it zeros the upper 128-bits of all SIMD registers, and is functionally has no execution cost on modern processors as it all happens as part of decode in the register renamer it's required to avoid a perf pessimization that happens when mixing "legacy encoded" and "vex encoded" SIMD instructions, as the legacy encoded have a merge behavior that must preserve the upper 128-bit results
-- please feel free to tag me on things when my name comes up I try to check in every now and then, but pings let me know there's something I can look at specifically