This is kind of the same reason 16-bit installers were a thing for NT software. In the mid 90s when NT ran on four different processor architectures all of the

This is kind of the same reason 16-bit installers were a thing for NT software. In the mid 90s when NT ran on four different processor architectures all of the non-x86 platforms had emulation for 16-bit x86. So MS recommended that you bootstrap your install with a 16-bit process that checked it was running on a 32-bit platform (i.e. not 16-bit Windows) and then launched the appropriate 32-bit installer for the CPU.