From handbook (-kernel files): Write down the names of the kernel and initrd as you will need it when writing the bootloader configuration file. It was true in past, when we were using grub legacy, but now, to install grub we just need to write grub2-mkconfig command and not bother with names. So, why write down these? Well, it may be needed only if you select GRUB legacy option, but it is "not recommended" now (in major architectures) Reproducible: Always
Not for amd64 and x86 anymore, that's correct (unless you use LILO). The paragraph is now updated for those architectures that the kernel name should start with the proper prefix so that bootloader tools can detect them automatically.
