

Boot means initramfs plus kernel. Any other part could do that, doesnt need to run in kernelspace. I dont think the initramfs runs in kernel mode either.
Linux is a big huge thing that is all very highly privileged. It works, very well, but it is kind of a security mess.














Yes, the kernel doing hardware things and another part doing rendering for example, interacting with the kernel.
Text mode isnt just the kernel… the first thing that starts after the kernel is the init system.