Not a developer in the field, but I believe generally the HLSL isn’t packaged in the game. Instead an intermediate format called DXIL is produced at build time from the HLSL, and that’s what is packaged.
Ah, sorry, then I carried over an assumption from OpenGL (where GLSL is actually what's packaged, or at least was a couple of years ago when I last looked at it).
In any case, that intermediate representation is probably still easier to compile to hardware-specific code, especially if the hardware has a Direct3D implementation. That's what it's designed for, after all!
Technically true but if you are going to use SPIR-V you might as well jump over to Vulkan. Do you know of any OpenGL games that actually ship SPIR-V? I can imagine it getting used in CAD applications with huge legacy OpenGL code bases but for Games OpenGL+SPIR-V doesn't really have a good use case.
In any case, that intermediate representation is probably still easier to compile to hardware-specific code, especially if the hardware has a Direct3D implementation. That's what it's designed for, after all!