I agree with you, but even with legacy booting, without using UEFI, there is no need for a boot partition, or at most you need a boot partition of a few tens of

I agree with you, but even with legacy booting, without using UEFI, there is no need for a boot partition, or at most you need a boot partition of a few tens of MB. The boot partition does not need anything else besides the kernel (without modules), a config/menu text file and a minimal boot loader like syslinux. Complicated boot loaders like grub have been obsolete for decades. I prefer to not have any partitions on the SSD with the Linux root file system and to boot from a normal FAT-formatted USB memory (which stores the 3 files mentioned above), which can be edited on any computer, using any operating system. If you want to boot a computer both in Windows and in Linux, there is no need for a boot menu. It can boot in Windows without the USB memory and it can boot in Linux by inserting the USB memory and selecting it as the boot device (typically the BIOS uses some function key for that).